I kinda thought most people would say it is easier to get than to keep, however, I am beginning to wonder the more I think about it. I have known or heard of many women who stick around with guys who are objectively total losers, bums, moochers, or even abusive men. It seems that these guys can get away with much more than a guy can get away with in the initial dating phase.
Here is one example-a friend of mine started out as a normal guy who had a beautiful fiance. However, he became addicted to an online computer game (World of Warcraft). He started playing this game to the exclusion of all else, including his friends and girlfriend.
Me and his girlfriend had some talks about this over coffee(at her initiation), and she would tell me what was happening in their relationship. He had lost his job, she was paying all the bills, doing everything except potty training the guy. He became nocturnal, generally getting up in the afternoon and staying up all night on the computer, he had repeatedly even turned her down for sex(and she was an HB9!) when she tried to seduce him. This went on for several months before the relationship finally fell apart over some chick he apparently met online. Eventually he cannot pay the rent on his own without work so he just moved in with his mother.
I think it may have been fairly easy for me to have made a move on her at the time she was complaining about him, but I have a "code of honor" where I will not steal a freinds girlfriend(but at that time I wonder if he even would have cared). I have heard similar stories about men being bums or even abusive towards their girlfriends yet these often times beautiful women will stick around with them.
Contrast this to my recent dating experiences. The first one was with a woman I met online, and on the first meeting the convo was going well at first but somehow it ended up by me mentioning that I enjoy playing a video game call Rome Total War every once and awhile, and sometimes I will get together with a friend and play computer games for the night on his computer network. Me playing a game casually for a few hours a week or getting together with friends one night a week is not the same at all as a 27/7 addiction. However, her attitude immediately grew sour and she let it be known that there are no video games allowed in her "household", and that grown men don't play video games, only little children. Needless to say, I am not going to let a woman boss me around like this and tell me that I cannot play ANY computer games EVER.
Another woman I met online, we were talking about various subjects, and she mentioned in one sentence that when you die you cannot take it with you. I agreed but told her I was signed up for cryonics(those people who have their body frozen in the hope that future medical advances will cure their cause of death). She was aghast, but I told her that it made perfectly logical sense, and besides, I wanted to see what the future would be like anyway. She thought it was selfish and went against God and the natural order or some B.S.
The third date wasn't an online date, I actually met her through work, and I thought she probably liked me. One friday she invited me to dinner with her, and when we were talking during dinner the discussion moved to art and I told her I liked to draw. When she asked me where I learned to draw, I told her that my ex girlfriend taught me to draw really well and I learned out of some of her art books.
Immediately after mentioning the word "ex girlfriend" her attitude changed and things did not work out. It is not like I complained about my ex to her or anything, I just referenced our relationship once, but I guess that was enough to change her mind about me. Then I have been on several recent dates where I have no idea how I bombed. Then there are a number of women recently I have exchanged an email or two with on myspace and then they quit emailing me, leaving me tearing my hair out wondering what I said wrong in the last email.
My point is that it seems these women in relationships put up with alot from their men, but in casual dating any little nitpicky thing can ruin any chances you have with a particular woman. Therefore to me it seems it may actually be more difficult getting into a relationship than keeping one, and you have to be a total bum and screwup to lose a girl you are already in a relationship with.