Read this article from Nicolas Prudhon.

“Learn how to pick your own battles. This may sounds like a joke for many of you, but this is the primary reason why many sites or online businesses fail online.

Having a niche marketing strategy, that is focusing on a specific topic rather than a broad query allows you to perform better as you are competing with much less other sites on internet. In addition your visitors would tend to be much more targeted and convert better.

Getting yourself into an overly competitive market is a recipe for disaster and a way to ensure that your site will never be found. On the other hand, entering into an overly niche market may result in insufficient traffic volume to monetize your site or store and ensure your survival. Remember, because you think you got a great idea doesn’t mean that other people share your feelings!”