Boys suck, because they have too much testosterone, and they don't think with their heart. They think with other things. They think short term instead of long term. Guys in general are thinking about what can happen within two days or even a week, not what can happen within a year or in the distant future. Because of this, it makes it easy for them to hurt the feelings of their female counterparts. Looking at it in a girls perspective, when one guy does something wrong to a female, it makes the female believe that all guys are the same.
When girls think all guys are the same, it makes girls feel less comfortable dating or talking to a guy or getting close to a guy, because they feel like that guy in particular would treat them the same way the last guy did. Thus, meaning that the majority of girls feel as if a guy is going to talk to them for a certain amount of time and do them wrong because of their last encounter with a male. When girls begin to feel this way, it begins to make guys feel as if they are being sterotyped.
Guys have issues with girls when they are stereotyped, because no guy wants to be put into that category of "pieces of crap." Guys want to be viewed as good guys, and they don't all want to be stereotyped as bad. Guys want to be treated with respect, and they want to have a girl who respects them.
I think that personally, all guys and girls should have respect for each other no matter what. Guys are rude and so are girls, so I think everyone needs to start respecting each other a little better and everybody will be happy!