Dan begins by saying that most lifters fall into the trap of thinking that they missed a deadlift simply because they didn't pull hard enough or because they weren't strong enough in their glutes or their lower back. Dan says that this is a mistake. To demonstrate why, he talks about two ways people usually miss on a deadlift: right off the floor or at lockout. Often times the same issues cause both; a lot of lifters use poor technique and let themselves pull out of position from the floor, which in turn makes it nearly impossible to lock out the lift at the top. Your hips can only finish the lockout if they stay in position the whole way through the lift. If you're out of position and can't engage your hips because of it, improving your strength will not solve the issue.