Beatles taught me a lot about productivity than any book

First of all, they were consistent, which is far more important, with Paul being the most active member. According to Paul, they never took it seriously; had they taken it seriously, they would have been under constant pressure, which indeed affects productivity.

Brian Wilson was totally the opposite of the lads, which is why he suffered too.

Next, they didn't care about small details such as a wrong note or a voice crack in the final recordings; these small details do matter, but what's more important is the music. This here shows the 80/20 always matters, no matter what.

Third, they didn't reject the ideas or overanalyse anything; they accepted the ideas and would start working on them right away. Steve Jobs mentions how he was so inspired by the takes of Strawberry Fields Forever; he noticed how they would start with again and again until the direction they would be heading in sounded right. He said he used this mindset to develop Apple products.

And finally, detachment is the key; even if you love something, you should be detached; attachment will only whirl your mind down. This sounds very zen, but John was one of those people who focused on getting the job done; I think he was, most of the time, in flow and let the tide take him wherever it went.

Flow state is the way for anything in life. Love you, John! I am very much inspired by John; he wrote, "I am only sleeping" or "nowhere man" just observing himself, that's flow state I believe.