Burnout doesn't always look like "I can't get out of bed." Often it looks like quiet competence with a slow erosion underneath. Six signals worth paying attention to before the big crash: You start optimizing for invisibility. You used to volunteer for visible projects. Now you find ways to keep your head down. The shift from "want to be seen" to "want to be left alone" is one of the earliest signals. Sundays start feeling like Mondays. Anticipatory dread arriving 12-24 hours before the workweek is your nervous system flagging an unsustainable load. Small annoyances feel disproportionate. A Slack ping that wouldn't have bothered you 3 months ago now triggers a 20-min recovery period. The annoyance isn't the problem; the depleted reserve to absorb it is. You can do the work but you can't think about the work. You can still execute, but you stop having ideas, opinions, or curiosity about your domain. Output stays steady; generativity collapses. You lose your tells. The hobbies, the workouts, the calls with friends, they don't disappear all at once, they just slowly drift to "I'll do that next week" until next week is six months ago. You start fantasizing about specific exits. Not "I'd love a vacation" but "I'd love to quit, drive cross-country, and disappear for 6 weeks." The specificity of the fantasy is the signal.
If 3+ of these land for you, the response isn't "push through." It's: a real conversation with your manager (or yourself, if you're solo) about sustainable load. Burnout is fixable early and brutal late. Catch it at signal 3, not signal 6.