Maybe I’m not reading that right or didn’t catch it, but it doesn’t sound like all cars’ planks were checked during scrutineering. From the same document:
A physical floor and a plank wear inspection was carried out on car numbers 01, 16, 44 and 04.
So all the cars were subject to various inspections, but not all had the same things inspected. In particular, only cars 01 (VER), 16 (LEC), 44 (HAM), and 04 (NOR) were selected for plank wear inspections. And as such, only cars 16 and 44 were found to be out of compliance.
Am I understanding that correctly?
This is standard for how they do technical inspections. They can’t check every rule on every car, so they check just a few important ones for every car (fuel, weight, etc) and then do random checks on a handful of cars each for others. The idea is to prevent it from being worthwhile to break the rule, while also requiring substantially fewer resources. That’s probably also why the penalty is so steep: if it was a slap on the wrist that you had a small chance of being caught for, you might as well just always run out-of-spec.
It’s fair, but if they’re finding cars fail the checks, then all cars on the grid should be checked for the same failure.