I don't fear success. May be its the thought of the unfamiliar. I'm used to getting nowhere, but if all that suddenly changed radically. I'd be like
what happens now. I'd also be happy
to get somewhere and have financial security for myself and to support relatives. And maybe once you become successful you will feel more pressure to maintain that success, with the bar being raised which can be even harder.
I also sometimes think that If you achieve your dreams, It might not live up to what you imagined it would be like. (Maybe it would). As you ask yourself what to aim for now?