I tend to agree with the others above, though the only times that the programmers were blamed on my team (That I am aware of anyway...) were electrical issues.
Once last year, the driver complained that he couldn't drive. The joystick was plugged into the wrong port on the DS because of a hurried dash to replace a broken DS. (Dang ethernet ports!)
The only other error was a missing fuse, it was taken out while some debugging was performed, but forgot to be replaced
