30 Trading Never-Dos: Lessons Every Trader Learns The Hard Way

1) Never oversize. That is when you start becoming irrational. Blowing up while still being right is the fastest way to ruin.

2) Never trade when tired or sleep-deprived. Decision fatigue has ended more traders than liquidation ever could.

3) Never trade without a defined edge. Entering without one is just gambling with extra steps. If you can’t explain your edge in a single sentence, you probably don’t have one.

4) Never enter a position out of boredom. The desire to always be in a trade leads to suboptimal returns. More often than not, doing nothing is the best move.If you find yourself taking trades just to feel busy or because you «haven’t traded in a while, ” check yourself. Trading for action leads to sloppy decisions and losses​.There’s no prize for the most trades — only for the most profitable trades. Sometimes the best trade is no trade

5) Never trade after a big loss. Tilt sets in, and you try to win it all back in one bad bet. Trying to recover everything at once is a guaranteed way to lose even more.

6) Never enter a position without an exit plan. Whether it’s a time-based stop, price stop, invalidation, or catalyst-driven exit—define it before you enter. Remember, the last moment of objectivity is before you place the trade​.Once you’re in, it’s much harder to admit you’re wrong, so decide beforehand when to cut the loss.

7) Never marry your bags. The market doesn’t care about your conviction. Cut or be cut.

8) Never trade your PNL—trade the market. Chasing losses or fixating on past wins clouds judgment and distorts execution.

9) Not all views are meant to be traded. The best trade is often no trade. Preserving capital and mental bandwidth for when odds favor you is more important than forcing activity.

10) Never fight the trend. The wave is stronger than you. Adapt or get wiped out.

11) Never try to knife catch without reason. «Cheap» can always get cheaper.

12) Never break your trading rules or deviate from your plan in the heat of the moment.​ Your rules exist for a reason — usually learned from painful experience. The moment you convince yourself «just this once» to ignore a rule (like moving a stop, or doubling down, or trading too big), you open the door to chaos. Discipline is doing the right thing even when it’s hard. As one trading maxim goes, plan the trade and trade the plan.

13) Never fire all your bullets at once.

14) Never trade outside your comfort zone. If a position is too big, you’ll start making fear-based decisions, thinking that market or someone is trying to liquidate you seeing ghosts where none exists. Size your trades proportional to the quality of your sleep at night.

15) Never let ego keep you in a bad trade. Admit when you’re wrong—cut, reset, move on.

16) Never underestimate market reflexivity. Strength can always go higher, weakness can always go lower.

17) Never assume liquidity will be there when you need it. The exit door is always smaller than you imagine—liquidity isn’t something you decide, the market does.

18) Never mistake randomness for strategy. Buying because price is going up or shorting because it «feels high» isn’t trading—it’s blind betting. Even with good risk management, you’ll bleed out over time if your entries are based on nothing.

19) Never make the same mistake twice. Trading mistakes are inevitable, repeating them is unacceptable. Never lose the same way twice

20) Never forget to play defense. Being wrong is acceptable, staying wrong is not. Protecting capital always comes first. «Don’t focus on making money; focus on protecting what you have.»

21) Never just focus on offense. Survival > everything. If you don’t bet, you can’t win. If you lose all your chips, you can’t bet.

22) Never fall into lifestyle creep after one big win. The problem starts when you begin forecasting annual income based on a single lucky trade.

23) Never forget to turn defensive after a hot streak. Big losses come after a series of wins when overconfidence sets in. Check your ego—your last big trade means nothing to the market.

24) Never let pride, ego, or overconfidence take over. Always stay humble.|

25) Never trade in situations where you don’t have control. for eg. FOMC events

26) Never get complacent. A strategy that worked in one regime may stop working in another. Trading is a craft that requires continuous self-improvement. Comfort Is Often the Enemy of your PNL. Never assume you know for sure what the market will do. «We have two classes of forecasters: those who don’t know — and those who don’t know that they don’t know.”​ Never assume your edge is permanent. Markets evolve, edges fade, and what worked last cycle may be useless in the next. Keep refining, keep testing—stagnation is death.

27) Never ever average losers after your reasoning has been invalidated

28) Never trade with certainty, trade with conviction.

29) Never assume the market «must» do something, especially based on recent patterns.​The market doesn’t owe you continuity or logic. Just because a market has been rising (or falling) steadily doesn’t mean it can’t abruptly reverse. Avoid words like «surely» or «can’t possibly» in trading. Stay flexible — anything can happen. As a reminder: never say never about market behavior.

30) Never mistake win rate for everything. Maximizing winning trades for the sake of feeling good is a trap. Taking profits too early or avoiding necessary small losses ultimately hurts profitability.