I have charging set to 80% but phone charges more. Why?

[ozziegn]

I just received my 17 Pro Max. I set everything up and I set my charging limit to 80%. I left the phone alone for a little while and I come back to see the charge was at 92% and still charging. Why didn't it stop at 80% like I set it to?

 

[zackattack784]

This is why.

About Charge Limit and Optimized Battery Charging on iPhone - Apple Support

To improve the lifespan of your battery, your iPhone learns from your daily charging habits.

support.apple.com

 

[Paddle1]

As said in the link above: If you have Charge Limit set to less than 100 percent, your iPhone will occasionally charge to 100 percent to maintain accurate battery state-of-charge estimates.