Odds question...

[obisponator]

Hi guys, I am trying to explain to my friend pot-odds, and I can't give him a good explanation of why when you calculate pot odds, you don't include the chances that someone else at the table either has one of your outs or it was already folded. Can someone give me a quick and easy explanation for why you do not include cards that were dealt to other people to adjust your outs, and please dont say because there is an equally likely chance that they do have the card as if they don't. Thanks.

-Obi-