PPDA flatters teams that nobody wants to attack

The pressing metric divides by opponent passes, which means it rewards you for facing a side with no interest in playing forward.

Passes allowed per defensive action has one job. It tells you how many passes the other team gets to make in their own build-up before you interfere. Low number, aggressive press. That is the reading, and for a while it was a useful corrective to people who judged pressing by how loud a crowd got.

The trouble is the denominator. PPDA counts the opponent's passes, and an opponent chooses how many of those to attempt. Play a side that is happy to go long from the goalkeeper and your PPDA collapses, not because you pressed better but because they refused to give you passes to press. Play a side that keeps the ball in a back three for two minutes at a time and your number balloons even if your forwards are sprinting themselves into the ground.

Which makes PPDA close to useless as a league table. It is fine as a within-season trend for one team against roughly stable opposition, and it falls apart the moment you use it to rank sides across different competitive positions. The bottom club that everybody attacks and the top club that everybody sits against are being measured with two different rulers.

There is a second problem, and I think it is the bigger one. A defensive action in the definition includes a foul. Cynically kicking a midfielder on the halfway line counts the same as winning the ball cleanly. A team that presses badly but fouls constantly can post an excellent PPDA while conceding a set piece every eight minutes, and no version of the metric will tell you.

If you want a number for pressing, ask a narrower question. Where did the sequence end. How far up the pitch did we regain, and how often did that regain turn into a shot within ten seconds. Field position of recovery is crude, but nobody can inflate it by fouling and no opponent can distort it by going long.

None of this means the concept was wrong. Somebody had to put a number on pressure and PPDA was the first honest attempt. But the analysts who built it were clear about its limits, and the people who now quote it in scouting decks mostly are not. If a metric changes meaning depending on whether your opponent wants the ball, it is a description of the fixture, not of your team.