When people form an opinion or idea on/about something or someone and think that it is fact and set in concrete, instead of being open to listening, learning and possibly adapting their ideas over time.
Had it yesterday with a contractor where I work. I KNOW i'm right because I created the damn 'thing' that we were talking about in it's entirety! I tried to explain this but he kept repeating 'No, that's wrong. Listen, i've been a contractor for over XX years and...'.
Even when I tried to move on or minorly skirt around it (kind of irresponsible to do this as the 'thing' could easily kill him) by asking him to do specific things, he replied with things like 'Listen buddy, I have my own systems of working and i'm sticking to them...'
Sure, stick to your systems of working and get crushed in the machinery/cut in two... I won't be the one cleaning up the mess!
WE'RE THE ONES PAYING YOU, 'PAL', SO DO AS WE ASK! Hate to stereotype, but the older guys are terrible for being stuck in their ways. Can't take advice from a younger guy because their pride makes them deaf, dumb and blind! ARGHHHH!