Who can attest to this...
As soon as you are good at something and show any skill or enthusiasm for something, some people are simply going to hate you. Happens a lot at jobs, for instance. If one employee is too popular, there are always a smaller fringe group of haters mixed in there who quietly scheme and spread negative feelings toward that person.
Another example is the critic. There was a poignant documentary within the last couple years featuring comedians and performers who are heckled and their thoughts on the subject. A lot of them express pure confusion and distress in regards to these people who, apparently out of nowhere and for no reason whatsoever, can't stop talking about how much they can't stand them. They do their comedy or their music, which they made because they loved and have a gift for it, and then there's people saying "that guy sucks" or "I hate that guy's music" all the sudden. Look on almost any youtube video and in the comments section you'll find pure hatred spewing from people who somehow think they are so important and awesome that they, despite not having put anything out themselves (or simply loudly release a constant stream of crude ignorance), nor having ever even talked to you, feel justified to make sweeping negative generalizations about you and your efforts.
A few reasons behind it all (sorry if they overlap a little):
1. People feel instinctively terrified and jealous when one person in their midst starts getting too much attention. We start to wonder "what is wrong with me ... if people aren't gathering around me I'm losing control." We might even worry about being forgotten completely.
2. We think, I look bad in comparison to that person. He is more talented than me and everybody knows it.
3. It is a somewhat sharp reminder that we might be fundamentally inferior. At least in some ways.
4. People want everyone to be on the same level. They can't stand anyone above them in any way. Some people are such psychopaths they can't even stand anyone being different at all, let alone on a different level. They'd bully a disabled person. It makes them feel powerful. All of this could be described as a pathetic, delusional attempt to feel powerful.
You hear a lot of rappers talk about this in the songs themselves. Haters are a reality of success. I'm just sayin', I think it's important to know because when some people hear the haters, they believe them. They let those people keep them down. They give up on their gifts/talents because they don't know why these people would even be motivated to spew such hatred, other than it actually being true. But the truth is, those assholes are just plain jealous.
Also found highly in the work of Ayn Rand, especially the Fountainhead. Rand's work is great partly because she recognized something many of us are now well aware of: people hate you if you're smart. They try to undermine you if you are successful. They claim your work as there own, and do as they please with it to whatever extent they can get away with.
In my science classrooms, I felt terrible for certain kids because they were ashamed to say the answers they knew and also to even ask questions, because it meant that they were actually following along and doing well. Those kids who get C's, D's, and F's.... whatever level they're at, that's the level they try to make sure everyone else is at. There were plenty of kids who were very smart, or at least smart enough, to really learn something and contribute, but they are all shut down, checked out. Hell, you don't even have to be smart! People hate you just for caring. This one girl in my first period last year, she asked questions that were super obvious and simplistic, but people would openly ridicule her for asking questions, tell her to shut up, stuff like that. YES I saw this, yes it is real, and yes I told them they were the ones who were stupid, not her.
Word to the wise--99% of the time you're being criticized (and you're NOT hurting anyone), it means you're doing something right.