Disclaimer: I didn’t read any smart books about this topic and I am not a professional in this area. Just some observations of mine.
For those who never experienced this feeling of burning out, you may leave now.
What I mean by burnout: a psychological state where you are not able to do what you normally do. There is no motivation, no energy and when you do it, you feel like you are falling asleep instantly. You feel like you need to stop doing what you do right now, immediately.
Now, some people say working too much is the reason.
I quite disagree. I think the reason is the absence of progress.
The absence of progress doesn’t directly mean what it says. It is relative. For e.g. when we work on a long-term project and do every day something, other persons perceive it as a huge progress, for you, it’s just yet another step on a long road. At some point, you start asking yourself where are you going and why. There may be no answer to this and you may feel depressed. This feeling will grow stronger and stronger and here we go — you burn out. You can’t work efficiently anymore.
So how even more work should help?
It is simple. Find an open source project(s) where you have no time pressure. A project you can make better every day and receive feedback from the community. It will give you an instant feedback of progress and internal satisfaction. You will come to the feeling that what you do is useful and gives you a purpose. Every time you lack the motivation to work on one project — switch to another. It will relax your brain like you wasn’t working at all.