When someone doesn't like you, and you want to change that, trying to appeal to what they like will only make it worse. Asking them for a favour, on the other hand, can be much more effective.
As self-delusion-loving blog You Are Not So Smart points out, this is because -- despite the way things may seem -- our actions determine our opinions about people and not the other way around. Here's why.
For many things, your attitudes came from actions which led to observations which led to explanations which led to beliefs. It is well known in psychology the cart of behaviour often gets before the horse of attitude. Your actions tend to chisel away at the raw marble of your persona, carving into being the self you experience day-to-day. It doesn't feel that way though. To conscious experience, it feels like you are the one holding the chisel, motivated by existing thoughts and beliefs. It feels as though the person wearing your pants is performing actions consistent with your established character, yet there is plenty of research suggesting otherwise. The things you do often create the things you believe.
This happens because when you observe your own behaviour, you want and try to make sense of it. Generally you're unable to pinpoint the cause. When you can't, you look back on prior behaviour, or examine what you're currently doing, and associate it with a person or thing also on your mind. Negative or positive reactions, whether related or not, can have a very profound effect on whether you love or hate another. Ben Franklin, for example, turned one of his haters into a good friend by simply requesting to borrow a rare book. Franklin knew people, and knew this request would turn their opinion around.
For all the details, more studies, and tons of more interesting information about why this works, be sure to read the full post over at You Are Not So Smart.
The Benjamin Franklin Effect [You Are Not So Smart]