Revenge trading

Opening an unplanned and usually larger trade right after a loss to win it back; it turns a small loss into a big one.

The emotional trigger is anger and a sense of unfairness. Symptoms: a new entry within seconds of a stop-out, rising lot size, trades outside the rules.

The rule: call it a day once you hit the daily loss limit or after two consecutive losses. Enforcing this rule at platform level (a prop firm limit, a broker's daily limit setting) beats relying on willpower.