Waiting for the perfect moment to do something is a form of procrastination.
If you start saying stuff like, “I’ll start when I’m done with whatever I’m doing,” then it’s helpful to define what ‘done’ means. If you don’t explain it, then the definition of ‘done’ will keep morphing into whatever’s on your plate. There are no bookends in daily life.
You have to push the red button and tell the bus driver your stop is coming up, or you will keep on going wherever that bus is heading. That is why you hear people say that getting fired was the best thing that happened to them because it forced them off the wrong bus.

Excellent advice. The best is the enemy of the good.