Error Rate
also Rate of Making Mistakes · Weighted Error Rate
The weighted frequency of mistakes an activity generates, which must stay below your capacity to correct them.
Error rate is how fast an activity, project, or lifestyle generates mistakes. CF treats it as a weighted quantity: a few high-stakes errors can outweigh many trivial ones, so what matters is total severity-adjusted error production over a period (often a day or week), not a raw count.
The central CF claim is comparative. Your error rate must stay below your capacity to correct errors — the time, energy, focus, skill, knowledge, and other resources you can bring to fixing things. When error correction keeps pace, problems stay mere bumps in the road and projects reach successful conclusions. When error rate exceeds correction capacity, you are overreaching: attempting work too hard for you, which is inefficient at best and usually ends in failure.
Borrowing from Goldratt’s Theory of Constraints, CF adds that errors arrive with statistical fluctuations (Murphy strikes unpredictably), so you cannot safely run at 100% of capacity. CF recommends a buffer — a rule-of-thumb 1/3 of capacity reserved — scheduling work that produces errors at roughly 67% of your correction capacity, and raising the safety margin further if you keep failing, since people chronically underestimate error rates and overestimate their resources.
The practical upshot, developed under error rate management, is to seek easy: easy means efficient, well clear of your limits, with capacity to spare. You lower your effective error rate not by trying harder but by building skill so that formerly hard tasks become small — favoring incremental progress through successes rather than learning by a string of failures.