[nyar]

That one negative review costs money.

Beyond that - Googling the name of the business will almost always show a Yelp link below and will display the star rating within the search results. Bad stars = no business.

[jobu]

According to Amazon: "Even a product with negative reviews sells better than a product with no reviews at all." (http://www.npr.org/blogs/money/2013/10/29/241372607/top-revi...)