I phone 11

Batteries degrade with use, 93% is actually a pretty good score for an iPhone 11. When it reaches 80% Apple recommends replacing it.

Here is some good reading about your phone's battery and how to get the most out of it.

https://support.apple.com/en-us/HT208387

"phone 11: Hello I’m using I phone 11 my battery percentage was a last month 98% now it showing 93% how can I Increase the battery percentage"

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iPhone's Guesstimation:

It's just a guesstimation of percentage. I've seen reports of it increasing, even up to 100% from where it priorly was. So, no worries there. It's on the iPhone - no you.