Battery health does not change

[Basic75]

The "Maximum Capacity" under "Battery Health" of my iPhone XS shows 88%, which is not too shabby after more than three years. The reason I'm posting here is it has been at 88% for like the last two years which is a bit strange. Anybody else got a stuck maximum capacity? How reliable is this indicator?

 

[now i see it]

My 6 Plus has been at 93% or higher for 6 years. Original battery.
If you’re gentle with charging and discharging, the battery will outlive the useful life of the iPhone.

 

[Hish99]

Yeap my 11 pro max been stuck on 88% for last 3/4 months now. But my battery life seems lower than before. Might try a factory reset & after that a battery replacement