That's a quote from Yoda. Here is a similar one from Mr Miyagi in karate kid talking to his student Daniel, before they start training.
Mr. Kesuke Miyagi: Now, ready?
Daniel LaRusso: Yeah, I guess so.
Mr, Kesuke Miyagi: [sighs] Daniel-san, must talk. [they both kneel] Walk on road, hm? Walk left side, safe. Walk right side, safe. Walk middle, sooner or later, [makes squish gesture] get squish just like grape. Here, karate, same thing. Either you karate do “yes”, or karate do “no”. You karate do “guess so”, [makes squish gesture] just like grape. Understand?
Daniel LaRusso: Yeah, I understand.
Watch for yourself.
I think there are many interpretations of this quote — but in my mind the most important one is this: The only way to learn is to actually DO something 100%. Whenever you try something half-baked you give yourself a way out — I didn’t really try, I could do better — whatever.
It doesn’t matter if you succeed or not. What matters is the learning process. In order to get to that learning process the way it is meant to be done it is crucial to commit fully or not commit at all — otherwise, the data you get will be distorted.
For example, if you commit fully and fail you will learn valuable lessons. I find the best learning takes place when you fail miserably.
Not doing something is better than half-doing because you can then focus on doing something else fully. Or thinking about what you want to to do fully.
Essentially: Don’t waste time doing things half-assed. It will give false feedback on your capability and makes it harder to see the truth about your strengths and weaknesses. Its also easier to come up with false reasons why something didn’t go as planned if you didn’t take it seriously in the first place.
Thanks Yoda & Mr. Miyagi for the valuable advice!