Batteries have limited number of cycles before it starts to really degrade.I have batteries that are over 100% with hundreds of cycles
The more you cycle especially deep cycle any battery the more wear it puts on the battery. That's why those people who don't charge throughout the day and drain their battery from 100% to 5% every single day, need a new phone in a year.
I've had devices for many years that I constantly keep it topped up as much as I can. And down the road I haven't noticed any difference in its battery life.