Hotmail/MSN/Outlook mail is well known for just not delivering lots of legitimate mail now. You may not see spam there, but you may not get mail from a friend who doesn't use common webmail like gmail or Yahoo. The mail does not even go to your junk/spam folders, and it does not get bounced to the sender. They just silently accept and delete incoming mail, without any notification.
I'd, personally, rather see spam getting through than email become a useless technology that fades away because people can't rely on it anymore.