Sometimes it's hard for engineers. In college, I majored in Computer Science, and for an elective, I took Electronics for non-EE majors. The first half of the course was analog electronics which I struggled with, but everyone else appeared to be following along fine. It was the second half of the class, with digital electronics, where things flipped. Students would struggle with "5V is a 1? 5V isn't 1V! What's going on?" while for me it was, "yeah, yeah, I know this already ... "
