Post-it Notes came from a glue that wasn’t sticky enough. A failure for one job can be perfect for another.

A result is only a failure relative to what you were aiming at. Weak adhesive is useless for permanent bonding and ideal for something you want to peel off, so the property never changed, the question changed. Discarding a bad outcome too fast means never finding out what it was actually good for.

Keep the thing that went wrong in your last project instead of deleting it. The off-colour mix, the take with the strange timing, the code that did something unintended. Ask once a month whether any of it fits a different problem you now have.