I think people often focus on people's disabilities rather than their abilities. Maybe this is because they don't know the person very well and only judge by appearances. I think if you tried to know them more, you would find their abilities are far greater than their disabilities.
Then we have Suzan Boyle, who is currently number 1 in the US and UK charts. Her YouTube videos, and there are several of them, were viewed by a total of more than 15 Million people!
There is nothing more I can say.