It's your masterpiece. You've worked hard to put together an informative and interesting newsletter. Your current subscribers often write to tell you how much they enjoy it. Marketing your newsletter is the only way you're going to find new subscribers. Come up with an informative description that stresses the benefits of subscribing, and then start promoting.
Marketing takes a lot of time.
These services charge you for each subscriber they find for you. Not enough time to spend marketing - or a lack of desire to spend the time necessary to promote your ezine. Desire to build your subscription base as quickly as possible. Don't Be Shy - Introduce Yourself. One of the big advantages of having your own newsletter is the leverage it gives you with other editors.