Why is my iPhone not charging past 93%

Click on this link to read about optimized battery charging on your iPhone --> About Charge Limit and Optimized Battery Charging on iPhone - Apple Support

- With iOS 13 and later, your iPhone learns from your daily charging habits to improve the lifespan of your battery.

- Settings > Battery > Battery Health > Optimized Battery Charging

- When the feature is enabled, your iPhone will delay charging past 80% in certain situations.

- "With 80% Limit enabled, your iPhone will occasionally charge to 100 percent to maintain accurate battery state-of-charge estimates."

The answer may lie in this post --> When to charge your iPhone or iPad - Apple Community