I think some people here are being a bit arrogant saying that 'you should only date if you could marry that person'. Some people have the opinion that dating is specifically to find that out (and then decided after a while that yep/nope not what I want in a husband), and some think that (especially younger ones) you need to date to have fun in order to see how the opposite sex relate once in a relationship - most men and women do change somewhat when a dating relationship starts, believe it or not - just because they are one way when you're their 'friend' does not mean they are the same after you are their 'gf/bf'.
I've seen VERY harmful things happen with people whose intention, the minute they start dating people, is to get married to that person. EVERY little detail gets the fine tooth comb, and they forget that part of a relationship is FUN. Everything ends up being about attitudes, and behaviours, and 'ooo is he the one', instead of learning to relax and develop the relationship at its own pace. I'm just as guilty at this - I guess that's why I caution people who are all, 'oh I only date to get married'.
Now, that's fine if you believe that you should only date to get married, but don't pick on those who choose to date to learn more about the opposite sex, and what they actually want in a husband. There is nothing inherently wrong with EITHER idea - so long as sinfulness isn't being carried on with at the same time (which can happen in either form of dating).
I've had successful relationships, where marriage wasn't the original idea between us. I've had a VERY bad relationship, where marriage WAS the original idea. So I can see both sides. Right now, my relationship is one that we consider possible for marriage in the future, the trick is not hurrying it into a place where we could get engaged, when a lot of issues are still in the beginning stages of being discussed and worked through.
Ringu, what you said above is VERY simplistic in nature. It seems very easy on the outside to be able to go 'nope, bad character, get out', but sometimes, it takes a lot more effort to actually walk away. When it's something you've been used to for years, and you can't imagine NOT being with that person, it is VERY hard to turn and walk away. Sometimes, big inherent behaviours don't get displayed until you have been in a relationship for a long time, and by that point, you're so ingrained with this person, that leaving just seems too hard and too painful. Believe me, I've been there, and I have a feeling I'm not the only one to have stayed in a relationship cos of it's 'stability and comfort', even though it wasn't healthy...
Sasch