How many times can I reuse a shower towel?

Excuse me, could you please clarify for me how many times it is considered SAFE or advisable to reuse a shower towel? I've heard varying opinions on the matter and I'm curious to know if there's a general guideline or consensus among experts. Does the material of the towel make a difference? And should I be concerned about bacteria build-up or other hygiene factors? Your insights would be greatly appreciated.