Why does my mom never believe me?

Everytime my mom's too lazy to do things I have to do them but everytime i do, she says "are you sure?" (even for the simplest things) and does it herself. One time she told me to look up this college online and i said it wasn't there so she tried to look it up herself but she got the same results and wouldn't admit she's stubborn and nvr listens to other ppl but herself. Why does she always do this?