Risk of ruin: what the profit curve never shows

A winning strategy with bad sizing still ruins the account. The name of that probability is risk of ruin: the chance of reaching the point where continuing is impossible.

Three drivers of ruin risk

1. Risk per trade: the bigger it is, the shorter the road to zero.
2. Error rate: losing streaks exist in every strategy; you must survive to the end of them.
3. Martingale: doubling size to recover accelerates the ruin rhythm — SANJESH exposes this pattern in managers’ behaviour.

Reducing ruin risk

Smaller size, written stop rules, diversification, and behaviour monitoring. To see dangerous patterns in managed accounts, see SANJESH; for risk rules, the risk guide.

Frequently asked questions

Can risk of ruin be zeroed? No; but it can be shrunk: small size, diversification, written stops. The goal is “staying away from zero”, not “zero risk”.

How long can a losing streak run? Longer than is comfortable to believe. Your plan must survive the streak’s length.

How does SANJESH help? It exposes patterns that accelerate ruin (like martingale) in a manager’s behaviour; choosing with data gets better.

Can the probability of ruin be brought to zero? Not to an absolute zero; but it can be made so small that in your operation it is a rare event: small size, disciplined stops, and no size increases after losses. Your direction on these three is what decides — not promises, and not luck.

Summary

The profit curve is half the story; the other half is the chance of never reaching the story’s end. Read the full risk guide.

The three drivers of account ruin

• Big risk per trade: the short road to zero
• Losing streaks: you must survive to their end
• Martingale: accelerating the ruin rhythm
• Small size and diversification shrink ruin probability
• The profit curve is half the story

The risk guide and SANJESH: See it.