The Best Time to Buy and Sell

Aayra keeps a little row of pots on her balcony. Some hold flowers that are doing beautifully - bright, healthy, growing taller every week. A few hold sad, scraggly plants that never quite took, and one pot has a stubborn weed that snuck in and refuses to bloom. She has one watering can and only so much time. So here's the question: where should the water go?

If you've ever grown anything, the answer feels obvious. You pour water and care into the plants that are thriving, and you pull out the weed. But watch what people actually do - with plants and, far more expensively, with their money. They get nervous about the lovely flower. "It looks so good right now," they think, "I'd better cut it and put it in a vase before something spoils it." And they feel sorry for the poor struggling weed. "It's had such a hard time - surely if I water it a bit more, it'll finally turn into a flower." So they snip the healthy bloom and pour the water on the weed.

That is exactly backwards, and it is the single most common mistake people make with their investments. When a stock they own goes up, they rush to sell it - to "lock in the win" - as if a rising price were a reason to leave. And when a stock they own goes down, they cling to it, sometimes even buying more, telling themselves it's "due to come back," as if a falling price were a reason to stay. They cut their flowers and water their weeds.

This whole chapter is about fixing that one habit - about learning the real reasons to sell a stock, which have almost nothing to do with whether the price went up or down. Selling the thing that's working to hold on to the thing that's broken is like snipping your flowers and pouring the water on the weeds - do the opposite: let the healthy ones keep growing and pull out the ones that failed.

Let's get to the heart of the confusion. Most people believe the price of a stock, all by itself, tells them what to do. Up? Sell, quick. Down? Something's wrong, or maybe it's a bargain - either way, react. They treat the wiggling number like a traffic light telling them to go or stop.

But a price on its own is not a reason to do anything. It's just today's mood of a very large, very jittery crowd of buyers and sellers. The crowd is cheerful some days and gloomy others, and the number bounces around because of that mood far more than because anything real changed inside the company. If you let that bouncing number make your decisions, you've handed the steering wheel to the most anxious, most excitable person in the room. That's no way to drive.

So what is a real reason? Only two things genuinely matter when deciding whether to sell, and neither one is the price tag by itself. The first is the story of the company - the simple, honest explanation of how it makes money and why it should make more over time. The second is the price compared to the earnings - not the price alone, but the price measured against how much the business actually earns. A stock is worth selling when its story got worse, or when its price has run far, far ahead of what the business earns. Those are reasons. "It went up 20% and I'm excited" is a feeling. "It went down 20% and I'm scared" is a feeling too.

The difference between a reason and a feeling is the difference between a careful investor and a nervous gambler. If you did the homework properly when you bought, the honest reasons to sell are few - the story broke, or the price has floated absurdly above the earnings - and "the number moved today" is never one of them. Hold that thought; the rest of this chapter is really just two ways of unpacking it.

Picture your reasons to sell as a very short list pinned to the wall. There are only two lines on it, and everything else is crossed out.

Line one: the story got worse. When you bought the company, you had a plain sentence in your head - "this shop keeps opening new branches and each one makes money," or "people keep needing this everyday product and the maker keeps its costs low." That sentence was your reason to own it. A real sell signal is when that sentence stops being true. The new branches start losing money. A cheaper rival appears and steals the customers. The owners load the company with debt or start behaving dishonestly. The earnings, which were climbing, flatten out or fall for reasons that aren't going away. When the story breaks, you sell - not because the price dropped, but because the thing that made it worth owning is gone.

Line two: the price has run far ahead of the earnings. Sometimes the story is still fine, but the crowd gets so excited that they bid the price up to a silly height - much faster than the actual earnings are growing. Imagine a company earning ₹10 per share, and people happily pay ₹150 for it, then ₹300, then ₹500, while the earnings have only crept from ₹10 to ₹12. The price is now floating far above anything the business is doing. That gap is a real reason to sell - not because the number went up, but because the number went up for no good reason and now there's a long way to fall.

Notice what's not on the list. "It went up, grab the profit" is not there. "It went down, run away" is not there. "I'm bored of holding it" is not there. "A friend said sell" is not there. If your reason to sell isn't one of the two lines on the wall - the story got worse, or the price floated far above the earnings - then you don't have a reason. You have a feeling wearing a reason's coat.

Here's the piece that most people miss entirely, and it's what turns "sell for a reason" from a nice slogan into something you can actually use. The right reason to sell isn't the same for every stock - it depends on what kind of company you own. Just as Aayra wouldn't care for a fast-blooming marigold the same way she cares for a slow, steady money plant or a mango tree that only fruits once a year, you can't have one sell rule for every stock in your portfolio.

Companies come in a handful of different types, and each type comes with its own answer to the question "when do I sell?" If you sort each of your stocks into the right bucket first, the sell decision gets enormously clearer. Buy a company without knowing which bucket it's in, and you'll panic at the wrong moments and relax at the wrong moments. Before you can decide when to sell, sort the company into its type - a plodding slow grower, a big steady stalwart, a racing fast grower, an up-and-down cyclical, a broken-and-mending turnaround, or an asset play sitting on hidden value - because the type is what tells you what to expect and when to leave.

Look closely at two of those rows, because they're opposites and they carry most of the lesson. A stalwart - a big, steady, reliable company that grows slowly and surely - is one you're happy to trim after it's given you a solid gain, say 30 to 50%, and move that money into another steady company that hasn't run up yet. You're not abandoning the idea; you're rotating from one dependable plant to a fresher one. But a fast grower - a smaller company opening new shops or reaching new customers quickly - is one you hold on to even after a big gain, for as long as the fast growth keeps happening. Cutting a fast grower just because it doubled is the purest possible example of snipping your flower. As long as the branches keep opening and each keeps making money, the story is intact, and you stay.

Same portfolio, two stocks, two completely opposite sell rules - and the only thing that tells them apart is which bucket each one sits in. That's why you sort first.

Let's put real rupees down and watch the stalwart rule work. illustrative

Aarvi owns shares in a big, boring maker of everyday household paint - the kind every family buys when they redo a room. It's a classic stalwart: it won't triple overnight, but it earns money reliably year after year, and its earnings tend to grow around 12 to 14% a year like clockwork. She bought ₹1,00,000 of it because the price was fair - she paid about 25 times its earnings, roughly in line with how fast it grows.

Over the next two years, two things happen. The company's earnings grow just as expected - up about 28% in total across the two years, healthy and steady. But the price runs up much more: the crowd falls in love with steady companies that year, and her ₹1,00,000 becomes ₹1,55,000 - a 55% gain. Now she does the arithmetic that matters. The business is worth more than when she bought it, yes, but only about 28% more. The extra chunk of her 55% gain came purely from the crowd being willing to pay a richer price - she's now paying something like 34 times earnings for a company that still only grows in the low teens.

This is the stalwart's sell bell. The story didn't break - it's still a fine company - but the price has drifted ahead of the earnings, and, just as importantly, a stalwart is supposed to be trimmed after a solid gain and rotated. So Aarvi sells most of it, taking her ₹1,55,000, and moves it into a different steady company - a well-run maker of biscuits and packaged food - that is growing at a similar pace but whose price hasn't run up yet, sitting at a sensible 24 times earnings. She hasn't left the idea of owning stalwarts. She's just moved the water to a fresher pot. If the paint company keeps climbing on nothing but crowd mood, that's now someone else's risk, and she's holding a company with room to grow into its price.

Notice she did not sell because "55% feels like enough" or because she got scared. She sold for two real, nameable reasons: the price had floated ahead of the earnings, and the type of company she owned was one you rotate after a good gain. That's selling for a reason, not a feeling.

Now the opposite case - the one where the temptation to cut the flower is almost unbearable, and cutting it is the mistake. illustrative

Rohan owns shares in a small chain of South-Indian breakfast restaurants. This is a fast grower: two years ago it had 40 outlets, and it's opening new ones quickly, each one filling up with customers and turning a profit within months. He put ₹80,000 in when it had that early, hungry look. He knew his story in one sentence: "they keep opening new branches, each branch makes money, so the earnings keep climbing fast."

The stock does what fast growers do when they work - it soars. His ₹80,000 becomes ₹2,00,000 in under two years. And now the whispering starts, both from friends and from inside his own head: "You've made two-and-a-half times your money. Sell! Lock it in! What if it falls?" Every rupee of that gain begs to be snipped and put in the vase.

But Rohan does the thing the nervous gardener never does - he checks the plant, not the price tag. He looks at the story. The chain now has 90 outlets and is still opening more, still profitably; the newest branches are as busy as the old ones; the earnings have roughly tripled, which is why the stock tripled. The price, measured against those fast-growing earnings, is high but not insane - the growth justifies it. In other words, the flower is still healthy and still growing. The story that made him buy is not just intact; it's playing out beautifully.

So he holds. He does not cut a growing flower just because it grew. Over the next two years the chain reaches 160 outlets, the earnings keep compounding, and his stake grows again. Had he sold at ₹2,00,000 to "lock in the win," he'd have snipped the best plant on his balcony while it was still shooting upward - the classic, expensive error. The rule for a fast grower is simple and steady: keep holding the winner while its growth story is genuinely intact - you pull a plant only when it's failing, never because it's flourishing. The day to sell a fast grower is the day the new branches stop filling up, or the openings slow to a crawl, or the price finally floats far above even the fast earnings - not the day your gain gets big enough to feel scary.

We've watched two winners handled well. Now the harder, sadder case - the losing stock people cling to - because knowing when to let go is where most real money is quietly lost. illustrative

Haridya owns shares in a company that makes cheap smartphone accessories - chargers, cases, cables. She bought ₹1,20,000 of it with a clear story: "it's the low-cost supplier everyone buys from, and it earns a small, steady profit on huge volume." A fine reason to buy.

Then the story starts breaking, quietly at first. A bigger rival begins selling the same accessories cheaper, and Haridya's company starts losing its price advantage - the one thing the whole story rested on. To keep customers, it slashes its prices, and its thin profit turns into a loss. To stay afloat, it borrows heavily, so now there's a pile of debt where there used to be a pile of cash. Each quarter the report is worse than the last: sales shrinking, losses growing, debt climbing. The single sentence that made her buy - "the low-cost supplier that earns a small steady profit" - is simply no longer true. A cheaper rival took the "low-cost" part, and the "steady profit" became a loss.

The stock, naturally, falls - from her ₹1,20,000 down to ₹70,000, then ₹50,000. And here is where the gardener's mistake grabs her. She doesn't want to sell "at a loss." She tells herself the falling price makes it a bargain now, so she pours another ₹40,000 in to "average down." She's watering the weed - and worse, using fresh water to do it. The price falling was never the point. The point was that the story broke: the reason she owned it had evaporated. Selling for a reason would have meant getting out the moment the low-cost advantage was gone and the profits turned to losses - near ₹70,000 - and putting whatever was left into a company whose story still held. Instead she chases the price down, adding good money to a broken business, and watches ₹1,60,000 shrink toward ₹40,000.

Compare her weed to Rohan's flower. Rohan held a stock that tripled because its story was thriving; Haridya held a stock that sank because its story was dying. To the nervous eye, the lesson looks like "the one that went up was good and the one that went down was bad" - but that's reading the price again. The real difference was the story, and the price merely followed it. Rohan held for the right reason (thriving story) and Haridya should have sold for the right reason (broken story). Neither decision was about the number on the screen.

There's one more selling reason to make solid, because it's the sneaky one - the case where the story is fine and you should still sell. It's the second line on our wall: the price has run far, far ahead of the earnings. illustrative

Think of the price and the earnings as two runners tied together by a long rubber band. Normally they run roughly side by side - as the earnings climb, the price climbs with them, and the band stays loose. That's healthy. But every so often the crowd gets giddy about a company and the price sprints far ahead while the earnings jog along at their normal pace. The rubber band stretches tight. And a stretched rubber band always does the same thing eventually: it snaps the runners back together - which means the price falls hard until it's near the earnings again.

Here's a composite to feel it. Aarohi owns a fast-growing maker of health drinks. For two years the story is genuinely great - sales rising, new flavours selling, earnings up nicely. But the crowd goes wild. The stock, which she bought at 30 times earnings (already rich, but the fast growth roughly justified it), gets bid up to 80 times earnings, while the earnings themselves have only grown maybe 40%. She started with ₹90,000; it's now worth ₹2,70,000. The company is still good. But the price now assumes the company will grow like a rocket for a decade - an assumption almost no company can live up to.

This is a genuine sell reason, even with a healthy story. Aarohi isn't selling because the number got big and made her nervous; plenty of stocks with big gains are fine to hold. She's selling because the price has detached from the earnings so far that even continued good news can't hold it up - the band is stretched to snapping. She takes her ₹2,70,000 and moves on. Sure enough, when the growth eventually cools from "rocket" to merely "very good," the price falls by half as the band snaps back - and the ₹2,70,000 she'd have watched slump to ₹1,35,000 is instead safely invested elsewhere.

The tricky part is telling this apart from Rohan's restaurant, where the price also tripled but he held. The difference is precisely the rubber band. Rohan's price tripled because his earnings tripled - the band stayed loose, price and earnings running together. Aarohi's price tripled while earnings grew only 40% - the band stretched dangerously tight. Same-looking gain, opposite decisions, and the thing that decided it was never the size of the gain. It was the gap between the price and the earnings.

Almost every selling mistake comes from letting the price - that jittery crowd-mood number - make the decision instead of the story and the earnings. It shows up in two mirror-image ways, and both feel completely natural in the moment.

The first is snatching at gains. A stock you own goes up, and a little voice says, "Grab it before it slips away!" So you sell a thriving fast grower after it doubles, feel briefly clever - and then watch it double again without you. You cut the flower. The cruelty here is that this mistake feels responsible, like you're being careful with your winnings, when really you're chopping down the very plants that were meant to make you rich.

The second is refusing to let go. A stock you own falls, its story visibly broken, and the voice says, "I can't sell at a loss - and look how cheap it is now, it must bounce." So you hold a dying business, maybe even pour more money in. You water the weed. This one feels like patience and courage, when really it's a refusal to admit the reason you bought is gone.

Now the honest cautions, because "hold your winners, cut your losers, sell only for a reason" can be pushed until it breaks.

The first trap is turning "hold your winners" into never sell anything that's up. Rohan held his restaurant chain because its story kept thriving - but that's the condition, not a licence to hold forever with your eyes closed. If those new branches had started sitting half-empty, or the price had floated to 80-times-earnings like Aarohi's health drink, holding would have flipped from wise to foolish. "Water your flowers" means water the ones that are still growing. A flower that has quietly turned into a weed - a former winner whose story has broken - must be cut like any other, no matter how much you loved it or how much money it once made you. Loyalty to a stock is not a virtue; loyalty to the story is.

The second trap is the reverse: turning "cut your losers" into panic-selling anything that dips. A good company's price wobbles all the time for no real reason - the crowd's mood, a scary headline, a bad week. That is not the story breaking, and selling a fine company just because it fell 15% one month is simply cutting a healthy flower that happened to droop for an afternoon. The test is never "did it go down." The test is always "did the story go down." A falling price with an intact story is often a chance to hold calmly, or even buy more; a falling price with a broken story is a signal to leave. The number alone can't tell you which - only looking at the business can.

And the third, quietest caution: none of these sell rules save you if you sorted the company into the wrong bucket to begin with. If you thought you owned a fast grower but it was really a fading slow grower, you'll "hold the winner" right off a cliff. If you thought you owned a stalwart but it was actually a fragile turnaround that never turned, you'll wait patiently for a recovery that isn't coming. Getting the category right is the foundation the whole sell decision stands on - which is why you do that sorting carefully at the start, when you buy, and check it again whenever the story shifts.