when to consider database replication dont forget it might be important

hey folks, i've been thinking a lot about scaling databases lately. weve hit a point where a single master is getting a bit strained during peak hours, and im wondering about the tipping point for introducing replication. like, what are the key indicators you look for that signal its time to set up read replicas or even a multi-master setup? is it purely load, or are there other factors like availability or disaster recovery that push you to replicate?