Why does the macbook itself discharge by 10% and continue charging?

Question

macbook

Hey! Observed in the morning an incomprehensible situation. Yesterday, the poppy pro 16 "worked from the mains all day, showed 100% charge all day. This morning it started to discharge, showing in the status bar: battery: power source not charging
: AC adapter

Discharged to 90%, after which the battery icon suddenly changed and started charging, showing in the line:
until fully charged left: 5:45
power supply: AC adapter

What could it be? Is it the poppy's standard behavior to accumulate recharge cycles? Or something else?

Answer 1

https://support.apple.com/en-us/HT211094?cid=mc-ol...