Lose twenty bucks on a lesson at eighteen so you don’t lose twenty thousand on the same lesson at thirty.

Small losses early are how you buy information cheaply. The lesson about trusting the wrong person, skipping the paperwork or believing an offer that was too good costs roughly the same either way; what changes is the size of the number attached when it finally lands. Learning it while the stakes are small is not failure, it is the low rate.

When something goes wrong at small scale, write the actual lesson in one sentence. Not a broad rule about people, but the specific thing you would check next time. That sentence is what you paid for.