For me (late 50s), I find that I don't feel productive as I use to be and can think of several reasons
* the project I'm on is not "mine". I joined a sub team of ~30 programmers who've been working on a 5 year project. I'm not familiar with the code. this in contrast to previous projects where I was a lead / main contributor. I wrote the initial implementation so I had a very clear view of the structure of the project in my head.
* the project I'm on is not a passion project. I got very luck that most of my career I got to work on things I wanted to work on so I had passion to make them great. my current project I don't feel that. I'm sure part of it is coming in late. I think it's great project but my heart isn't in it the same way it was for many past projects.
As a counter example, I got permission to prototype something on my own for a few weeks. I worked ~80 hours of over time those few weeks because I was so into it and I felt super productive because it was 100% my code that I understood, no waiting for code reviews etc... I appreciate code reviews but compared to prototyping without the feeling a productivity without is incomparable.
* my passion for coding seems to have dwindled. maybe this isn't true given the previous paragraph but coding things I used to spend time exploring I have a hard time working up enthusiasm for like I used to.
* the project I'm on is not "mine". I joined a sub team of ~30 programmers who've been working on a 5 year project. I'm not familiar with the code. this in contrast to previous projects where I was a lead / main contributor. I wrote the initial implementation so I had a very clear view of the structure of the project in my head.
* the project I'm on is not a passion project. I got very luck that most of my career I got to work on things I wanted to work on so I had passion to make them great. my current project I don't feel that. I'm sure part of it is coming in late. I think it's great project but my heart isn't in it the same way it was for many past projects.
As a counter example, I got permission to prototype something on my own for a few weeks. I worked ~80 hours of over time those few weeks because I was so into it and I felt super productive because it was 100% my code that I understood, no waiting for code reviews etc... I appreciate code reviews but compared to prototyping without the feeling a productivity without is incomparable.
* my passion for coding seems to have dwindled. maybe this isn't true given the previous paragraph but coding things I used to spend time exploring I have a hard time working up enthusiasm for like I used to.