One big thing is it's basically impossible to start doing research when you are 40 or 50 after spending 10 to 20 years not doing research. You might imagine tha

One big thing is it's basically impossible to start doing research when you are 40 or 50 after spending 10 to 20 years not doing research. You might imagine that you can, and I do know a few people who think they can, but no it's extremely difficult and basically not happening. Is there literally any highly cited journal paper with a first author who didn't do research for 20 years? Also, you have way more energy, drive, creativity when you are young and you just spent 10 to 20 years on other things instead of doing research during a time when you could have had the most impact.