What's more polite? If I'm busy, I don't answer the phone and let it go to voicemail so I can return the call when I'm free. I have friends who answer my calls everytime whether they are busy or not. If they are busy, they tell me they will call me back. I hate that! Because sometimes they forget to call back. I'd rather leave a message and have them call me when they get it. And I hate when people talk on the cell when they are checking out with a cashier, it's so rude and disrespectful to the cashier!