He is smart. There are many competing forces in a human being. Smartness doesn't always win out. You might even notice this in yourself some day.

Hans Reiser comes to mind. Very strong engineer, comically inept at defending himself in court.

Smart is not a number. You can be smart and dumb all at the same time.

He was on certain levels: https://en.wikipedia.org/wiki/Peter_Madsen_(inventor)

It's sadly common for people to be brilliant at one thing and hopelessly inept at others.

I have worked with a lot of people that were technically competent in a narrow field, but surprisingly clueless in most aspects of life.

It was sometimes a bit frustrating, since they could occasionally spend a lot of time on problems that had a simple solution for someone with some common sense.

I don't feel smart myself but generally get the big picture so I find it fascinating that smartness is multidimensional like that.

Hans Reiser[1] didn't do too well with the murder thing either, despite being (apparently) pretty damn smart w/r/t file-system internals.

[1]: https://en.wikipedia.org/wiki/Hans_Reiser