Why do Americans want to know the month first and the day second?

I'm sorry but it doesn't make sense TO ME. Based on what I was taught, regardless of the month, I think what matters first is to know what day of the month you are in, if at the beginning, in the middle or at the end of said month. After you know that, you can find out the month to know where you are in the year.

What is the benefit of doing it the other way around?

EDIT: To avoid misunderstandings:

• I am NOT making fun OF ANYONE.
• I am NOT negatively judging ANYTHING.
• I am totally open to being corrected and LEARN.
• This post is out of pure and honest CURIOSITY.

So PLEASE, don't take it the wrong way.