One example:
I had this guy, it was his second job, the previous one was about some Enterprise Java thing. Intelligent and hard working, and able to learn: we were exploring Erlang for some parts of the system and he was contributing within the month, with just a bit of hand-holding. But one day we get an urgent request for new functionality in the Java parts of the org, so I hand it to him. First task is getting some static data out of a few dusty html tables deep in the intranet and dumping it on a new table in the dev DB so we can start prototyping around it.
A couple of hours go past and I go check up on him. He's deep into some docs for an XML parser and ORM so he can parse the tables and get the data into the DB. He has already like 5 or 6 classes with all their getters and setters but he's not nearly halfway done.
I bring up the browser console, type $ to see if jQuery is loaded in the page, then come up with a one liner that spits the insert statements on the console (I had to google a couple of times, I'm not really a jQuery dude).
But then even that was a bit too flashy... he could just have coaxed the data into the database fiddling around with a spreadsheet and the DB GUI for a couple minutes.
But somehow his default and almost only mental model of interaction with data was overengineered Java, no matter how overkill it was for the task.