Almost nobody blows an account on a single trade. Accounts die slowly, from the same handful of mistakes repeated until the math runs out. Here are the five that do most of the damage — and why every one is a system problem, not a willpower problem.
1. Oversizing the position
The fastest way to ruin a good strategy is to bet too much on one expression of it. A 60% win rate is irrelevant if a single loss takes out 40% of the account. Position size is the only variable that controls how long you stay in the game.
2. No predefined exit
An entry without a defined exit is not a trade — it's a hope. Both stops and targets must exist before the position opens, because every exit decision made under live P&L pressure is statistically worse than the one made in advance.
3. Revenge trading
Revenge trading is the moment a trader stops following the system and starts trying to 'get it back.' It is the single fastest way to convert a controlled losing day into a destroyed week. Every blown account has a revenge trade in its autopsy.
4. No journal, no review
If you cannot show your last fifty trades on paper — entry, exit, size, reason, outcome — you do not actually know what you do. You have a vibe. Vibes do not survive contact with a drawdown.
5. No system at all
All of the above collapse into one root cause: the absence of a written system. With a system, oversizing is impossible, exits are predetermined, revenge trades violate a rule, and the journal writes itself.
How to fix all five at once
- 01Write the system on a single page
Entry rule, exit rule, stop, target, max position size, max daily loss. If it doesn't fit on one page, it's not a system yet.
- 02Cap risk per trade and per day
A fixed percentage per trade and a hard daily loss limit that ends the session. No exceptions.
- 03Log every trade the same day
Even three lines: what, why, outcome. Reviewed weekly. This single habit fixes more leaks than any indicator ever will.