My battery health is Very poor.. Now he 89 in only I have 8 months old
In only 8ths Months my battery health is 89 how it’s in Just 8 months
iPhone 11, iOS 14
Question marked as
Your battery health is not very poor. Batteries degrade over time with usage, that's just how they work. You can expect about a 1% drop per month with average use on an iPhone.
Apple recommends replacing it when it reaches 80%
Here are some tips on maximizing battery life.
https://www.apple.com/batteries/maximizing-performance/