The Worst Boyfriend in D.C.

So I was in the car last night on the way to Melting Pot with G, and we were listening to the radio. Unashamedly, we were listening to HOT 99.5. The "Freek Show" with Julian (who, by the way, has one of the most annoying voices a male could ever have, in my opinion) was on. The night's competition was for DC's worst boyfriend. To which G casually interjected, "maybe I should call in too." We laughed it off. Soon the women started calling in with their respective horror stories.
My goodness. We were both shocked and amused at the same time. Take, for instance, this one young lady, whose boyfriend, I'm sure, was definitely in the running for top dog (pun intended). The list of horrors read like a pathetic excuse for a Hollywood bad boyfriend character. This list included, but I'm sure was not limited to, always conveniently "forgot" his wallet when eating out, the days he remembered he would "treat" her to the Dollar Menu at McD's, and once, he showed up drunk to a dinner with the young lady's parents.
Okay, the extreme nature of the story aside, where the hell do these ladies find these guys? Furthermore, what exactly is the appeal? The caller mentioned, at one point, that she thought she could "change him" and that she could see "his potential." Oh please. The always forgetting his wallet should be a dead giveaway.
Another story was about this one young lady who had been dating her (now ex) boyfriend for six years. Then one day he said, "I love you." The next day he disappeared (presumably on some hedonistic adventure). On the third day (forgive me for the phrasing) he broke up with her.
Anyway, we never did find out who the worst boyfriend in DC was. Apparently the coveted prize was a live call to the offending party in order to force them to participate in a broadcasted declaration that the lucky winner was indeed the worst boyfriend in the Washington, D.C. Metropolitan Area. The idea being that it would effectively remove him from having any possible future chance with a lady.

Questions for discussion:
1.) Where do you draw the line between "has potential" and "drop like a bad habit?"
2.) Is this characterization transferrable to the opposite gender (i.e. females)?
3.) Have you had similar experiences, whether personal or second-hand? Discuss.
4.) What is the cause for the seeming prevalence of losers?