Bought my previous iphone in early 2018. Changed the battery this spring because its health reportedly fell below 80% of its maximum capacity. I could not care

Bought my previous iphone in early 2018. Changed the battery this spring because its health reportedly fell below 80% of its maximum capacity. I could not care less to be honest. Always charged to 100%. Dropped the phone multiple times throughout its lifetime. Fully discharged at random. Exposed to 50°C and direct sunlight as well as well below zero. 5 years is a good job done for a non-replaceable battery. And the cost of replacement was like 50usd or something in apple store. The question is: why should I start bothering?..