One of the key points of getting maximal results and not overtrain is to use proper progressive overload. Many trainees or gyms don't really have a plan. The plan is "just go up" or wing it. That only leads you so far and it's less than optimal. If you want to ensure continuous progress use the 2 by 2 rule of profession which simply means that if you get two additional reps on your last set for two consecutive workouts go up in either reps or weight. For example Robert is supposed to do 4 sets of 8-12 reps at 200 pounds and he gets 14 reps on his final set for two workouts in a row Robert should go up to 220 pounds (10%) and do sets of 8 working his way back up. For some this method takes longer, but for the patient that apply this the results don't platue due to overtraining. Your best athletes are disciplined. They realize moving forward slowly will always beat stopping.