Comment by Zelphyr

I don't know about when typewriters were new, but up until recently, many people were actively scared to use a computer. I worked with people who would physically shake when they would use a computer because they terrified of breaking something.

The mouse, while designed to help quell those fears, was still a part of the computer and still scary to those people.

The number of buttons probably didn't matter in the whole scheme of things. They would've been afraid of it regardless. But his instinct was already to remove anything from a design that wasn't absolutely necessary. So it fit with his way of thinking to suggest that people wouldn't use a mouse with two buttons. If eliminating one button could make those people less afraid of the computer, then that was the way to go.

All that said; I too thought that mouse sucked. But I was a power user by then and it wasn't designed for me.