Mechanism
Entry is optional. Exit is mandatory.
Many strategies look good because they assume exits at printed prices with full size. Real exits happen against a book, under time pressure, with spreads widening.
As you scale, exit liquidity becomes the limiting factor. What worked at small size fails at larger size because your own orders move the market.
When stress hits, liquidity retreats exactly when you want it. That is how “good trades” become drawdowns.
Edge is not only finding moves. It is surviving exits.
Practical framing: the market is a feedback system. Your job is to remove the behaviors that produce the same loss pattern, not to “feel better” about it.
- Turn recurring mistakes into hard gates.
- Reduce degrees of freedom when you’re losing.
- Make the next decision simpler than the last.
How it kills accounts
Strategy works small → size increases → exit liquidity becomes limiting → adverse fills / partials → drawdown deepens → margin pressure → forced liquidation.
How it kills accounts:
- The rule exists only in your head.
- Stress arrives and you improvise.
- Improvisation becomes inconsistency.
- Inconsistency becomes random results.
- Random results become a slow bleed.
Rule that survives
Design exits before entries.
Assume worse fills in stress and size accordingly.
Scale only to the point where exits remain realistic, not just where entries are possible.
Rule that survives:
- Write the trigger in observable terms.
- Write the action in one sentence.
- Write the penalty for breaking it.
Example archetype
You build a profitable approach on small size. Then you scale up and discover you can’t exit without moving price. The strategy didn’t die. Your liquidity assumptions did.
Tell: if your rule isn’t enforceable, it’s a suggestion. Suggestions don’t survive stress.
Deep dive
What to do instead
Take liquidity seriously: liquidity, market impact, partial fill. These are not jargon. They are constraints.
This is why Liquidity is there until you need it is a core truth, not a slogan.
Related
Field checklist
- Write the rule in observable terms: if X, then Y.
- Remove choices under stress. Choices become rationalizations.
- Track the precursor: what state were you in before the mistake?
- Make deviations costly (size down, pause, review).
- Turn lessons into gates, not notes.