There has been an ongoing debate over the years about whether or not it's necessary to feel some passion about the products you're promoting or the markets you're working in. The market that any given product belongs to will go far to determine how you feel about selling that product, or service. If a particular market does not interest you, then you may want to think about if you'll be happy working with it.
The reason for this is when you're doing affiliate marketing, you'll have to promote the products using various marketing methods and if you're not excited about the product, how will you sell it? If you're heart and enthusiasm is not present, then quite often people will be able to see right through it. You don't want to torpedo your own efforts in a situation like this. So that is something you'll need to think about when you're evaluating a market and product. Never think that your audience will be unable to tell how much you're really interested in their problems.
Many newer marketers have difficulty with some of the finer points of choosing an effective domain name. First of all, if you're trying to target one single product, then you need to have a dedicated domain name for it, one that contains the main keyword. Don't settle for free web hosts that give you a sub-domain name. Regardless of how you're marketing, you'll want to have a domain with the primary phrase in it for best results.
Hopefully you understand the importance of solid market research before you get too involved with a project, among other things you need to learn the problems of your market so you know what to address in your marketing. You will find your efforts producing excellent results if you have accurate knowledge of what your audience is looking for, and then you figure out how to give it to them.
So just think about what good research can do for you regarding your knowledge about your target market. There are many affiliate products that will not sell very well, for different reasons, but some marketers still try to promote them. If you develop a blog with your market, you can get feedback about a lot of issues and concerns on their minds, and then you can do something about it. You could also employ polls on different pages on your blog, or static site, and ask different questions so you can get an excellent idea of what's on their mind.
All in all, affiliate marketing is not rocket science. You'll have to get educated and take action no matter what you do, but the rewards are there for you to take. It's more than possible to do nothing but affiliate marketing and make tons of money.