Had a friend of whom it was said: "He may not always be right, but he's never wrong!"

He was a very smart, clever and dedicated guy who was usually 'right' in his facts, decisions and understanding of sitations.... maybe 95% of the time. The problems arose in that other 5%..... he just couldn't quite absorb the idea that he might be misguided, mistaken or plainly wrong.
He was also very good at arguing for his weaker positions, and was almost never directly combative or insulting...(he had a fairly important job for many years). In his work, he had the position that allowed him to 'win' most debates... and was well respected for his high % of good decisions. It was very hard for him to deal with being questioned in his private life... he expected to be 95% right all the time, and still had problems with the 5%. Those who knew him well managed to shrug and wait for him to 'adjust' his own thinking.... those who didn't often viewed him pretty negatively and sometimes balked at him even when he WAS right.

I'll bet many of us know someone similar.