why women apologize

If you're anything like us, you say these two words way too often. Here's when an apology just isn't warranted.
I didn't realize that the habit of starting sentences with, "Sorry, but could you..." actually made me present my own needs as weaknesses. It was probably clear to the other person, but the reason it wasn't clear to me was because the word "sorry" had subconsciously made me feel as if I was constantly bothering other people.
Are we apologizing in order to navigate our way through a still-sexist workplace, where issuing normal demands and requests can still brand a woman as "difficult" in the eyes of her coworkers? Are we apologizing to appear more likable? Are we genuinely stepping on a lot of strangers' feet?