I've also seen quite a few instances where the person needed fundamental corrections for their problems before their main problem could even be addressed, and they absolutely refused to accept those basic corrections first. It makes it impossible to help them with their real problem.
The tech support example of this is when the phone tech requires someone to reboot the device before they'll continue diagnosing the problem. I only worked phone tech support for a year, but in that time I had quite a few people who thought they knew better and refused to reboot the device when asked, but when I forced them to do it, the problem fixed itself. When it didn't fix it, I was able to get on with the rest of the diagnosis.
When I first took that job, I even let them refuse to reboot. After a handful of times that I couldn't figure out what was wrong because it made no sense, and finally rebooting fixed it, I followed the company line of requiring the reboot up front after all. OTOH, I did believe them when they said they rebooted it already. If they lied about that, it generally caused it to be a very long, frustrating call for them, and my call times were already too short, so I didn't worry about it. (Yes, too short. My call times were low enough that it looked like I might be just getting people off the phone without fixing things, though of course none of my recorded calls showed that happening. My boss literally told me to chat with the customers more.)