I took and then TA'd a class where the semester long project was to control robots (it was a software engineering principles class, the actual code writing could be done in a single weekend, but you had to do all the other stuff of software engineering- requirements analysis and documentation etc).

We had a software simulator of the robots, and the first lab was everyone dutifully writing the code that worked great on the simulator, and only then did we unlock the real robots and give you 2-3 minutes with the real robot. And the robot never moved that first lab, because the simulator had a bug, and didn't actually behave like the real robot did. We didn't deliberately design the robot that way, it came like that, but in a decade of doing the class we never once tried to fix the simulator because that was an incredibly important lesson we wanted to teach the students: documentation lies. Simulators aren't quite right. Trust no one, not even your mentor/TA/Professor.

We did not actually grade anyone on their robot failing to move, no grade was given on that first lab experience because everyone failed to move the robot. But they still learned the lesson.