I was told reading was my problem too...except I was only nearsighted in one eye. My right eye couldn't focus clearly past the length of my arm, but my left one

I was told reading was my problem too...except I was only nearsighted in one eye. My right eye couldn't focus clearly past the length of my arm, but my left one had no trouble at all. For years, I wore a plain lens for the left eye, and when I was old enough, switched to wearing only one contact lens. They confirmed it wasn't that I was reading only with my right eye, and it's obviously not like my eyes got different amounts of sunlight, given that they go everywhere together, so I've always been suspicious that that was a lazy answer.