Rarely if ever does the word "always" apply to anything.
Most "nice guys" tend to have low key or introverted personalities. Where as the "bad boy" stands out, comes across as confident, exciting, unpredictable, mysterious, and usually is considered good looking and he (knows) it. The "bad boy" is a challenge!
I have often said if you stick a woman in a room with five men and four of them get down on their knees extending their heart to her while the fifth guy sits in a corner sipping his cocktail and acting like she does not exist.....that will be the guy she wants to get to know! LOL! These women subscribe to the old quote:
"We adore those who ignore us and ignore those who adore us."
Lots of women go through their "bad boy" phase BEFORE they settle down with a "nice guy". Thus the expression "Nice guys finish last". In other words the nice guy has to (wait) for the woman to experience numerous heartaches and disappointments with the "bad boy" before she will give a "nice guy" a chance. Some of these guys refer to it as getting the "left overs".
However it has also been said that nice guys clamor for the "hot chicks" or "b^thces". One woman author wrote a book advising women to behave that way in order to attract men. Apparently "nice/good girls" have the same problem of attracting the kind of men they want to be with as well!
Maybe "good girls" and "nice guys" are not attracted to each other! :-)