I feel like every concept can be taken too far or is expected to perfectly encapsulate every situation.

The few principles I live by are vague to avoid that predicament-

1. Don't let the perfect be the enemy of the good 2. Under promise, over deliver 3. Graveyards are full of indispensable men

1 took me a long time to really learn

2 In my case, where I've sucked at estimations, it's really not over deliver, but deliver my under promise.

3 is a De Gaulle quote and my favorite - when I think I can't be replaced because I've had an ego boost from a recent accomplishment. Alternatively, it can also be interpreted as 'the world goes on'.