Always have a product that's not just 'you'

...you should always have a product that's not just 'you'. An actress should count up her plays and movies and a model should count up her photographs and a writer should count up his words and an artist should count up his pictures so you always know exactly what you're worth, and you don't get stuck thinking your product is you and your fame, and your aura.

Andy Warhol, Fame

Always find the 'why'

From 'The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win' by Maria Konnikova:

It’s only a few months ago that [poker player] Phil Galfond reminded me to always find the why behind every move, every decision, every action. And here’s one thing I know for sure: no matter the decision, the why shouldn’t ever be for the simple glory of saying you’ve done something. At least to me, right now, that’s not good enough.