My usual preset sets are done, usually 4 or 5 of them per exercise, regulating the weight so that on my final set I am struggling on the last 2 reps. Done, but I know I can do more. I can hit a short set with a heavier weight. Bam… short set done, difficult but done. Wait, I have a few more left in me… Raise the wait once more.. Struggle, really struggle for 2 or 3 reps, done!!! Any more and my form will be off and not only won’t it be worth the reps, it would also risk injury… I have more… Drop the weight to the same as my first or second set, push out 15 or more until I can no longer perform the motion…. Move on to the next exercise and repeat.