Being overworked also has negative psychological repercussions, some of which won’t be evident for a while. You may start to resent your tasks and doubt your motivation to do them. It’s a vicious cycle—the more tired you are and the less enjoyable the process, the slower you go and the more mistakes you make. You make the task harder for yourself. The next time you approach the task, you’ve already taught yourself that it’s hard and unenjoyable and that you’re going to be slow and make mistakes. So, what do you do? Push yourself to be “disciplined” and slog even more.
Go a little further down this path and eventually you end up burned out.