when do you think about a load balancer

hey everyone, im working on a project that's starting to see some decent traffic, and im wondering about the tipping point for introducing a load balancer. right now, were still on a single server, but i can see that becoming a bottleneck soon. at what point do you typically decide to bring in load balancing. is it purely based on traffic volume, or are there other factors like server health checks or managing different types of traffic. im curious.