Not sure what you are talking about. I was only talking about cars that are close to the threshold of being totaled. Most shops are in business to do repairs and make money. If they can keep a job and "move the goalposts" later (within reason), why wouldn't they, rather than trying their hardest to get the vehicle totaled and not make any money (or very little). It doesn't matter if they can start working on the car right away or need to schedule an appt for a later date. Again, I'm not clear what your formula is for ensuring a car is totaled when it is close to the threshold. Also not sure what "keeping" the car has to do with anything. Some shops are busier than others and if a car is driveable, it is not uncommon for some shops to tell you to keep driving it while they process the claim and order parts.
What you described is basically how things work. You take a vehicle in for an estimate or make an appt with an adjuster, they do their thing and review, then decide to proceed or total.