Every cleaner has something called a pH level. Some cleaners, like vinegar, are acids. Other cleaners, like bleach, are the opposite, called alkalis. Both of these are destructive to natural stone, especially in a wet shower. Acids eat the surface, and alkalis eat the protective coat.
The secret is to use a cleaner that is not an acid or an alkali. It is right in the middle. This is called pH-balanced. A pH-balanced cleaner does not use strong chemicals to clean. Instead, it uses special ingredients that gently lift up soap scum, hard water spots, and body oils. Then you can just wipe them away.