It's called pooled hiring, and it makes sense when a company is hiring lots of people for lots of teams. Most large companies do this when hiring rates are high. You end up with better employee-team match when you interview a candidate first and then match them based on their skills/interest, rather than contacting them for a specific role they may or may not be interested in.
Has nothing to do with whether hiring is for headcount or other reasons
Has nothing to do with whether hiring is for headcount or other reasons