Let's imagine that 99.9 percent of soup cans don't have botulism after usual treatment. If you're the 1000th customer, you're in for a deadly surprise. If hospitals transfuse blood crossmatched at 99.9 percent, the 1000th patient gets a transfusion reaction that could kill. In short, 99.9 percent isn't always good enough.
The 'simplest' play has executable dimensions.
For example, in the SLOB above, against man-to-man defense:
1) Play must trigger on time.
2) 2 has to empty the ball side.
3) 4 must screen properly.
4) 5 must set up cut and get separation off the screen.
5) 3 has to look off defender and make accurate pass.
6) 5 has to catch the ball.
7) 3 must cut hard to get separation.
8) 5 must deliver pass on time and on target.
9) 3 must finish.
Ideally, you have continuations...e.g. 4 down screens for 1 if the initial action doesn't play out...
We can't assume automatic action...we see poor screens, players who don't wait don't set up cuts or cut hard. Players don't catch the ball or pass into traffic, and so forth.
The analysis shows that on this "simplest" in-bounds play, players have to execute well to even get a scoring chance. The Patriots' mantra "do your job" has to marinate into the TEAM consciousness.