The laptop turns off after a while in sleep mode. Bug or feature?

Question

Windows

I noticed that a few hours after being in sleep mode, the laptop turns off. At the same time, if after some time after being in sleep mode it turns off to open the lid, it will turn on (faster than if you turn it off after shutting down and turn it on), although if you turn it off after shutting down, it will not turn on when you open the lid. The fact that it turned off can be understood by the indicator on the lid.

Answer 1

feature:
first sleep, then hibernation