It's obvious. Every time you search the Internet you see it for yourself: the huge difference in the designs of the sites you visit. Some look like they were created by million-dollar Madison Avenue agencies while others look like your 12-year-old nephew did it for his school project. And those are the visible elements. Look deeper, and you'll find other aspects of web design that affect everything from search engine optimization to visitor experience.
When it comes to *your* site, take the time to ensure your business will be well represented on the web. Sure, referrals from friends are great, and you should definitely get several referrals when you start your search. But you should also be armed with some carefully thought out questions to ask as well.