Why ask if you know the answer?

I usually ask even if I know the answer simply because I need confirmation. Thru this mistakes can be avoided.

I ask to clarify that my knowledge is correct or that science hasnt changed what i was taught recently (example the number of planets changed betweeen since i was in school and now) I also like to get other peoples opinions ideas...new things to try. Basically widen my scope of knowledge and borrow from other peoples experiences.