Why you can lose money even when the call was right

The stock moved the way you expected. The trade still ended in a loss. That is not bad luck. It is usually one of five other decisions going wrong. Every one of them can be named.

Published 6 September 2026 · Potoos Research Services

The five decisions inside every trade

When a trade goes wrong, most people check only one decision. Was the view right or wrong? But a finished trade is the result of at least five separate decisions. Any one of them can sink it on its own.

You can be right on direction and wrong on any of the other four. That is the ordinary way careful people lose money. The rest of this page takes them one at a time.

Position sizing: the decision that decides survival

Position size answers one question. If this trade hits its stop-loss, how much of my money is gone? Answer that before you enter, and a losing trade is an expense. Skip it, and one losing trade can set you back for months.

The failure pattern is sizing by conviction. The idea feels strong, so the position grows to match the feeling, not the plan. Then the arithmetic is unforgiving. Say a position is half your capital. It is stopped out 10% below entry. That one idea has just cost you 5% of everything you have. Losing streaks happen, so you will do that a few times in a row eventually. The account is damaged even if most of your calls were right.

Disciplined traders fix the most they will lose on one idea first. They set it as a fraction of their capital. That number then sets the position size. The exact fraction matters less than the rest. It has to exist. It has to be small. And it has to be decided before the trade, not during it. This is also why we suggest a minimum capital of Rs 50,000 for our own service. Below that, sensible per-trade sizing runs into subscription costs and minimum lot sizes. The arithmetic stops being sensible.

Entry discipline: chasing turns a good idea into a bad trade

Every idea has a price at which it makes sense. It also has a price at which it no longer does. This is why a proper recommendation gives the entry as a range, not a single number. Inside that range, the risk and the reward are still in the right balance.

Chasing is what happens when the price runs before you act, and you enter anyway. The direction call may still prove correct. But you now own it at a worse level. The distance to a sensible stop has grown. The distance to the target has shrunk. Chase far enough, and a trade built to risk one rupee for a sensible reward now risks two for very little. The view behind it is the same. The idea did not change. Your entry changed the trade around it.

The discipline is dull. If the price has left the entry range, the trade is gone. There will be another. Missing a move costs you nothing. Chasing one costs you money exactly when the view was right. That is what makes it so hard to spot afterwards.

Exit discipline: the stop you move is not a stop

A stop-loss placed before you enter is a decision made by the calmest version of you. A stop-loss moved during the trade is made by a different version of you. That one is watching money disappear. The first decision is worth something. The second usually is not.

It usually goes like this. The price falls toward the stop. Instead of exiting, you widen the stop, because the view still feels right. Sometimes the price then recovers. That is the worst outcome of all, because it teaches you that moving stops works. The time it does not recover, the loss is no longer the small planned one. It is whatever the market decided. And you now hold a position with no exit plan at all.

The same failure has a mirror on the way out of winners. You exit the moment a position shows any gain, afraid of giving it back, whatever the plan said. Both failures come from one root. The exit was rewritten in the middle of the trade. Whatever the direction call was worth, that rewriting took its place. This is why every call we publish carries its stop-loss and staged targets the moment it is issued. It goes out in writing, before the market can push you to change them. The full anatomy of a call is described here.

Slippage and gaps: the price you get is not the price you planned

A stop-loss is a trigger, not a guarantee. It is an instruction to exit when the price touches a set level. In a calm market, the price you actually get is close to that level. In a fast market, or across a gap, it is not.

The clearest case is the overnight gap. You hold a stock with a stop 3% below your entry. Bad news lands after hours. The stock opens 9% down. Your stop triggers at the open. The loss you actually take is three times the loss you sized the position for. Nothing malfunctioned. The stop did exactly what a stop does. The plan was still exceeded, because a stop cannot fill at a price the market never traded at.

Costs pull the same way. Brokerage, securities transaction tax, exchange charges, stamp duty and the bid-ask spread are each small. But they come off every single trade, winning and losing alike. The more often you trade, the higher the bar your direction calls have to clear just to bring you back to zero. A right call that clears the market but not the costs is still a losing trade.

F&O decay: right on direction, wrong on time

Options add a clock to every view. The clock is the part that catches people. An option's price is not only a bet on direction. Part of what you pay is time value. Time value melts a little every day. It melts faster as expiry comes closer. Traders call this theta decay.

So a call option can lose value while the underlying index moves in your favour. That happens when the move is too slow, or comes too late. Be right about the direction and wrong about the week, and the option expires worth less than you paid. Sometimes it expires worth nothing. The direction call was correct. The instrument punished the timing. Volatility does the same from another angle. Options bought when implied volatility is high can lose value even while the underlying index moves your way.

This is not a reason to treat derivatives as a trap. It is a reason to treat them as a separate skill, with a separate clock. SEBI studied individual traders in equity derivatives and published it on 20 August 2026. It found that 87.7% of them ended the year in the red. That number does not argue that F&O is unbeatable. It is evidence that direction alone does not carry an options trade. It also shows that anyone trading them without understanding decay is paying for that education in the market. It is also why our intraday F&O desk and our positional equity desk are separate subscriptions. They are different jobs, and nobody is pushed into derivatives to follow us.

Over-leverage: the same move, made bigger both ways

Leverage does not change the market. It changes you. Leverage means taking on exposure with borrowed money. It multiplies the effect of every price move on your capital, in both directions. It also adds somebody to the trade who does not care about your view. That is the margin call.

Leverage turns a right call into a loss by shortening how long you can stay in. A stock can travel to exactly where you said it would. On the way, it can dip deep enough to exhaust your margin. The holder with no leverage rides the dip out and sees the call vindicated. The leveraged holder is forcibly closed at the bottom of it. Same call, same chart, opposite outcomes. The only difference was leverage.

The rule that survives is the boring one. Size your exposure so that the ordinary noise of the market cannot force you out of a position the plan says to hold.

What this means for how you use any advisory

Everything above happens on your side of the screen. That is exactly why an honest research service is specific about what it controls and what it does not. We control the structure of the call. That means an entry range, staged targets, a stop-loss set before entry, and the reasoning in writing. You control the size. You control the price you actually get. And you control whether the plan survives contact with your emotions. No service can promise you an outcome, and we have written separately about what one can and cannot do for you. What a service can be is auditable. Every Potoos call is dated, kept, and never edited after the fact, with losses on the same screen as wins, inside the app.

And before you follow anyone, us included, verify the registration. Here is how to check any Research Analyst on SEBI's own register in about five minutes.

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