On the more general side, it's a bit hard to describe, just like it is hard to describe when someone "Googles bad".
They ask self serving questions, underspecify their requests, omit crucial context that the agent is blatantly not going to have access to, or subtly misdirect the agent. They expect the agent to figure out everything: you'll never catch them write a prompt longer than one or two sentences. They never steer the agent or look at the CoT traces.
My boss being a particularly poor case: he apparently has the habit of arguing with the agent, as if it was a person, as if there was any merit to that. Starts being a dickhead with it, shouts at it, what have you. Was flabbergasted we don't.
On the more practical side, they have zero mental model of the harness they're using (Copilot Chat in VS Code). They're surprised when the cheap-ass Auto model, which is almost always some beyond-demented version of GPT, does stupid things. They have no concept of skills, zero understanding of what an MCP server is, haven't heard of lifecycle hooks, agent memory, the various fs scopes (session, workspace, user). No concept of how to have the agent inspect its own debug logs for higher accuracy action provenance.
This also snowballs. Having to give them a stock config is one thing, but even beyond that, you won't see them experimenting. The MCP you're using doesn't support some action? They'll never interrogate whether the underlying scoped OAuth token or bearer token does support it, and they'll never ask their agent to patch the functionality in. They'll not consider the various user flows it can perform on their behalf. They'll not string them together into end-to-end automated workflows unless you explain it to them this is possible, and even after that, they'll just kind of ignore it. They'll never build tooling, extend the harnessing, etc.
Whether this has more to do with age or just disinterest-induced lackluster adoption, up for opinion.