Mechanism
During normal conditions, depth replenishes quickly and spreads behave. Under stress, makers pull quotes and depth collapses. Execution stops being “price” and becomes “availability”.
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
- You send a market order (or rely on a market stop) right as depth collapses.
- The best quotes disappear before your order arrives.
- You get filled across multiple levels, far from your intended price.
- Your risk model assumes the stop is a seatbelt. In a liquidity vacuum, it’s an airbag that may or may not deploy.
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
- Assume stops can slip. Size so a worst-case fill won’t end your month.
- Prefer limit, stop-limit, or staged entries when the tape is jumpy.
- If depth is unstable, treat the instrument as temporarily untradeable.
Rule that survives:
- Write the trigger in observable terms.
- Write the action in one sentence.
- Write the penalty for breaking it.
Example archetype
A data surprise hits. The chart prints a clean break, but the book is empty. You enter ‘at market’ and instantly wear the entire move.
Tell: if your rule isn’t enforceable, it’s a suggestion. Suggestions don’t survive stress.
Deep dive
Deep dive
A useful mindset shift: in calm markets you trade price. In stress you trade liquidity. The same setup can be A+ in one regime and untradeable in another.
Watch for the trio: spread expansion, quote flicker, and shrinking depth. When all three appear together, treat it as a switch flipping.
Glossary: liquidity vacuum, market impact, adverse selection.
Related: The first fill lies.
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.