Why do players call for sets?

Hey everyone, I’ve been playing recreational volleyball for a while, and one thing that I’ve noticed is that nearly everyone calls for the set on almost every play. I get that communication is key, but wouldn’t it make more sense for the setter to decide where to set based on the pass they receive and their scan of the court? Is there a deeper strategy behind calling for sets that I’m missing, or is it just a habit? Would love to hear your thoughts on this!