Time to hire measures a single candidate's journey, from the moment they enter your pipeline, by applying or being sourced, to the moment they accept an offer. It is a read on how efficient your process is for the people already moving through it, and it is one of the most watched numbers in recruiting because a slow process loses good candidates to faster ones.
The instructive thing about time to hire is where the days actually go. Very little of it is spent interviewing. Most of it is waiting: applications sitting unread, scheduling threads crawling toward a booked slot, decisions that nobody has quite made. That waiting is invisible on a calendar, which is why it goes unfixed, and it is where nearly all of the recoverable time hides.
Because of that, the way to improve time to hire is almost never to cut interviews or rush decisions, which only lowers quality. It is to close the gaps around the work: screen applications as they arrive, let candidates self-schedule, and give the panel a scorecard so the decision has what it needs to happen quickly. Remove the dead air and the number falls without the bar moving.