By wiping out everything, there is a good chance that the system will work again. Also, the technician can show his boss that he has handled another call expeditiously. No need to vent your spleen on that person. It is a management problem. The tech is insufficiently trained for the job.
Support is considered an undesirable cost center by corporate bean counters.
They don't worry about the future. It does not exist for them if they fail to meet the stock analysts' next quarter earnings expectations. She has to become as self-sufficient as possible. There are users' groups which are valuable for networking. They consist of people who are willing to share their experience.