There was an article posted by CBC last week about a car in Newfoundland that tried to steer itself into the oncoming lane after a windshield replacement.
The driver, while very surprised, had an easy time taking control and there was no collision or other damage. According to the article he had not been told clearly that a system calibration was needed after the windshield replacement.
The facility replacing the glass would have known that the calibration was needed but they also know that they do not get paid by the insurance company to manage the calibration process, with the result that it becomes a cost to the company. They will get reimbursed for the cost of the calibration, but they get paid nothing for the time spent getting the car to and from the dealership for the calibration or for the phone calls needed to set up the calibration appointment. This post from November 2016 goes into some detail.
It is easier and to either ignore the calibration, or tell the customer that they should take the car to the dealer for this work.
The insurance company paying for the claim would also have information that the calibration was needed. Insurance companies are quite good at catching a $75 charge for a part that could be bought on the aftermarket for $50. This suggests that their internal systems are well set up to track how claims are managed and submitted. They have to pay for calibration in many cases and these numbers must be tracked as well. So why do they not flag a submitted claim that does not have the calibration included?
For both parties above, the repairer and the insurer, there is to date no financial incentive to doing the truly complete repair. This Newfoundland case cannot be the only instance of missed calibrations which means that repairers and insurers have been getting away with it until now. They will continue to get away with it for some period of time, but as more owners become aware of how their cars are designed and how they have to be repaired the getting away with it will not be as easy.
My sense is that owner awareness is building.