This method is the traditional approach for Bodybuilders to maximize hypertrophy. It involves providing a large training stimulus (usually as part of a body part split in more advanced trainees), then allowing the body to recover and "supercompensate" by over-adapting to be able to improve performance the next time. Over time, this supercompensation returns to baseline, so you want to train that muscle again while it's still in the supercompensation phase, thus making it supercompensate to an even higher level, improving performance yet again.