Users don't always conform to the perfect visions of engineers
I knew a bunch of people who went to a school which was very selective and very high-tech. They had computer systems to do everything. All of the people who went there had accounts and used them often. This is a tale of a time when an engineer wanted one thing and the people wanted something else.
One of these systems was an electronic suggestion box which would be reviewed every week. Users could post their own questions, and other users could vote on them much like posts on sites like reddit. One interesting side-effect of the way it had been installed was that users could mask their identification. This way, someone could look like "Anon from building C" instead of "Jill Jones". Not everyone used it, but those who did seemed to have their reasons, and it seemed to work.
One day, things changed. Someone upgraded the server or changed a setting. First, you could no longer change what you appeared to be. That choice just flat-out disappeared from the posting screen. Worse, there was another change: old posts also showed this data! The system had actually been keeping this information all along, and when the switch was thrown, everything became visible.
Bad as that was, that wasn't the worst part. That came later, when one of the engineers behind the system was asked about it. He basically declared the system was never intended to be used in any anonymous fashion, so the users got what they deserved. This shows the complete disconnect between that engineer and the users.
It's pretty simple, really. The users had expectations of how the system would behave based on what they were doing and what they saw. There were input fields which let them fiddle with things, and the resulting posts matched what they had provided. They could even confirm it by looking at a post when a friend was logged in. At that point, it doesn't matter what some engineer's vision may have been. The user had their own expectations and intentions, and that takes priority.
All the while, the engineer was howling because his perfect vision had been violated. People wonder why nobody trusts computer systems and those who run them. When you hear stories like this, would you?