Becoming a prolific product creator can end up making you a lot of money, if you concentrate on producing quality products that people really want, enjoy and learn from. The idea is to build up a solid reputation of constant quality, that people will want to come back for time and time again and buy your future products too. You are not just building a product. You are building a relationship with your customers, nurture that relationship by always offering value and good customer service.
Keep things as simple as possible and always look at it from your customers point of view. Make sure your product is easy to read/view or listen to, and always make the delivery of the product as seamless as you possibly can, with as few steps as possible, both to purchase and to receive the product.