Many businesses thrive on single product. These businesses are often called single product organizations. This is particularly truer for small businesses. Large businesses can’t afford to be single product organization. Threats are too many and single product strength quickly gets translated into weakness.
Ditto for small businesses. If a small business owner is trying to survive and thrive on single product, this can only be on a shirt term basis. Of course, there are few exceptions to that, but mostly the successful businesses offer more than one variant to its customers. With more than one product on offer, you are fortifying your product line form current and future point of view.
There is another advantage in doing so. Customers ‘feel’ good when they select one of the two or three products. They ‘feel’ that they have taken a right decision by evaluating all the variants / products available, and took a final call on the purchased product.