Battery Maximum Capacity keep’s dropping

Hello

I have had an iPhone 14 Plus for 4 months now and 2 weeks ago I checked to see my capacity and it dropped from 100 to 99, which is normal, then the next following day it went to 98. I went to check on it last night and saw it get to 97 after updating my phone to the new iOS 17 like 3 days ago. I don’t know if the software update affects the battery life because as of this morning it’s at 96. I’ve been charging my phone from 20-80 percent but most times I, could be busy and leave it on the charger past 80 and sometimes leaving charging all night, but I don’t mean to do it. I’ve also never used low power mode until right now, which I feel maybe that’s why I could be losing battery health as well. I charge it 2 times a day and I do charge my phone at night as well and, as for my research, I’ve heard that it’s not good to charge it at night. I mostly use my phone for the media and most of the time games when I’m not using my iPad.

Most likely other iPhone users are experiencing the same or similar issue as well and would like to hear about it.

Thank you!

(added a photo for proof)