When you went to school and saw your janitor cleaning, did you look down upon them? Heck I remember in grade school when we all picked on the school janitors and gave them a hard time. I think we all did this as kids because we felt like they were a nobody because all they do is clean for a living.
Would you feel different about your janitor if he could sing like Elvis Presley?
I guess the moral behind this is even though we may think that a janitor is probably only capable of cleaning, they are in fact capable of a lot more.
You never know. Your janitor might become famous someday.