system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 why do mead and beer tools and containers need to be very well sanitized during the brewing process if both were created before people knew about bacteria?

I'm not so much questioning rather it's a good idea to stay clean or not but most guides I read or watch seem to indicate it will drastically alter, in a negative way, the results if you don't sanitize everything thoroughly. 

This seems strange as I would assume that monks back in the day would not have known to sanitize anything.
gpt
You can still make them without sanitizing, but the results can be terrible.

Before people knew about bacteria, they still learned (through trial and error) that some things come out much better if you wash your containers with boiling water before starting.