So after the tyre failures at Spa, the drivers berated Pirelli to such an extent that the powers that be (ie Bernie Ecclestone) had to take them into a dark room and explain the facts of life.
Basically, he said, "without tyres, you guys are out of a job, so keep it zipped".
Pirelli invested a lot of time and effort to find the reason for the failure Sebastian Vettel suffered at Spa. This is like sifting through the bits and pieces left over from a plane crash, when it can take years to identify the cause of the failure.