If you own a business, you need a website. Some business owners think the only reason to have a website is to sell your product on it. But that simply is not true. Having a presence on the web does far more than enable you to sell your product online. Your online business presence helps people find you, helps you advertise your product or service, allows you to answer questions when you are closed, and it helps people find you among other things.
So, the answer to the above question is this; once you launch your website you have to optimize it. Optimizing your website helps search engines find you and your product, lets people know basic information about you, such as where you are located and what you do, and it also helps to convert searchers to customers.