If you're beautiful, you're led to believe that you can't also be smart.
Look at Jessica Simpson. She's famous for being dumb. I guess it started with Marylyn Monroe, and she actually wasn't that dumb, but that's how she was perceived - and that's what got popular.
Believe it or not, lots of people change their majors and abandon their dreams just to avoid a couple of math classes in college.
Students never think it can be the teacher's fault and so I thought I was stupid. I was frustrated and would come home and cry because I couldn't do it. Then we got a new teacher who made math accessible. That made all the difference and I learned that it's how you present it that makes it scary or friendly.