From what I see, this is what lots of people believe atm. According to the "nice guy syndrome", a nice guy treats a girl nicely for something in return, while a good man is good to everyone only for the sake of being good. A nice guy is ethically questionable and a good man is desirable.

But my experience is, when I was around 20 I was a good man treating everyone nicely, but girls didn't feel they were special to me and they thought I was a fuckboy messing around. And when I started treating one girl extra nicely and making her feel special, I immediately fell into the definition of "nice guy syndrome". Later I also tried treating some girls badly while still being good to others, and, you guessed right, those girls thought I was a jerk and avoided me. The only thing I haven't tried is being a jerk to everybody but that's something I cannot do.

So my conclusion is girls don't really care about the difference of a good man and a nice guy.