Why or why don’t a woman take a man’s last name?

I had a poll that was just accidentally deleted but I thought I would clarify my question . obviously a woman has the right to do whatever she wants to do whether it keep her last name hyphenate her last name or change it completely to her husbands.

So many people get married with the number one thought is “ I can’t wait to change my last name to his” because that makes people believe that they are officially married. I didn’t change my last name to my husband yet I still am and feel married.

What are your thoughts on changing your last name or /and keeping your last name?