Considering over 90% of people start a search with google first. If people can’t find you by typing your company name into Google, that’s going to raise some serious alarm bells.
Your site allows customers to find out more about you, your product, and gather any information they need. Even if it's just the peace of mind that you have an online presence, this lets a potential customer start to take you seriously. A website is the first step in helping build a company-customer relationship.