Say “I always mess this up” enough times and your brain starts treating it like a to-do list.

Repeated statements about yourself work as instructions more than descriptions. Say something often enough and you begin noticing evidence for it, discounting evidence against it, and quietly avoiding the situations that would test it. The sentence does not even need to be believed to do this. It only needs to be repeated, which is what makes the offhand ones so effective.

Catch the phrase in the act this week and add two words to the end: so far. Then find one counterexample from the past year. This is correcting the record, not arguing yourself into optimism.