Many people think that the more associates they have signed up for their associate program the better. However, you should not approve anyone who wants to sign up for your program. Your focus should be on building a quality affiliate associate program, not just on getting the most numbers.
Good associates work for you and reflect on your image. For example, an associate who's using a free web site is probably not treating this as a business and won't do much for your sales. It takes time and money to monitor your associates, so eliminate the ones who are not producing for you.