Think about what happens when you search for a business online. You get a lot of listings besides just their website — and their site often isn't the first result you get either.
The same thing happens when someone searches for your business — they see a lot of listings, all showing your business information...and there's a good chance that some (or even most of it) is wrong.
Incorrect listings could have a negative impact on your search ranking too. Google doesn't like when online information about a business doesn't match or is inconsistent, so it's less likely to serve up your business in the results.