Perseverance. On Thursday, I was doing 10x3 bench press, but once the 7th set was done, I knew I wasn't going to get an 8th, 9th or 10th triple out. I was going to stop, but then opted to be less of a pussy than that, and get my last 3 sets in 4's with 5kg less. That was a nice success. I also accumulated 88 pull ups throughout the session.