The prevailing narrative holds that you should be willing to sacrifice things for your work.
Working late shows dedication to the firm. Responding promptly, even when you’re not at the office, demonstrates that you care. If your boss asks you to take on more work, the “best” employees will say yes.
For an extreme example of how this can go wrong, read or watch The Circle by Dave Eggers.
To some degree it is true that you have to make trade-offs to do good work. But you can sacrifice too much and hurt everyone in the process.
Who benefits when you only sleep five or six hours a night? Despite what many believe, if you were to measure your productivity objectively, you would get more good work done if you got eight hours of sleep.
And who benefits when you consistently work 60-hour weeks? If you worked 60 hours one week, you might be able to get some more stuff done. Maybe you could even do that for two or three weeks. But do it for a year, and you might burn out and not be able to work at all. Who benefits from that?
You will do better work when you get enough sleep, when you take plenty of breaks, and when you regularly get away from your work completely. In other words, when you are “selfish”—at least under that prevailing narrative.
In reality, there is no trade-off between taking care of yourself and being dedicated to your work. In fact, taking care of yourself is the best thing you can do for your work, too.
So be selfish at work. It will benefit everyone.