Do You Really Need to Rest in Between Sets?

There are a number of strategies we can use to make workouts even faster. The most obvious way to cut down on your training time total training time would be to just rest less time in between sets. I also like strategies like drop sets because they allow you to get a little more volume in in a shorter period of time. We don't honestly believe that if you rest let's say 30 seconds to a minute in between sets if we're taking those sets to muscular failure how much of a difference are we actually talking there right?