I've experienced burnout when I had to work outside the working hours (overtime) because I had deadlines to meet or I had to spend extra time studying a particular tech. But when I became a freelancer, I learned to manage my time, I learn the deep work. I work 4 hours (just deep work, no destruction), and in my spare time, I can do other things I am interested in, like blogging. I know this won't work in the corporate world (office-based job) but I hope one day the employers will realise the value of deep work.