What is error classification?

Example: You miss a deadline at work. Before you can fix anything, you need to diagnose what went wrong. Possibility one: you knew the deadline, had a plan, and simply forgot to set a reminder — an execution error, a slip in the mechanical act of carrying out what you already knew. Possibility two: you did not know the project had a dependency that added two weeks — a knowledge error, a gap in the information you were working from. Possibility three: you knew about the dependency, estimated it would take three days instead of fourteen, and chose not to adjust the timeline — a judgment error, a flawed assessment of reality. Same outcome. Three completely different root causes. Three completely different corrections. The person who treats every missed deadline the same way — 'I need to try harder' — will fix none of them.

This concept is part of Error Correction in the How to Think curriculum.