Submaximal Sets?

What does submaximal sets mean?

Sets that aren’t a 100% maximum effort. E.g., performing a set at 75% of a 1RM or a RPE 7 (three reps in reserve) are “submaximal.”

A dumb question I know, but Thanks

I had an idea this is what it was but still was about to ask the same question… glad I found an answer. Thank you