Is perception everything? Can customer reviews change perception about a business?

It can be everything. If you Google "old town mexican cafe san diego", you will probably find better reviews than any other place. It is a tourist location hence the perceived value is higher. The food isn't anything great, neither is the service. In fact, you probably won't get good service most of the times. But overall, people seem to say that it's a great place to eat. I don't think any amount of bad reviews will change the opinion of people decide to go there because of most of them seem to think ok and some of them think it's exceptional.

The question I am trying to ask is if reviews are the only way people believe in something. It's easy to answer- NO. Google reviews are only a guidance for people who are searching. Reviews can tell if something is horribly wrong with a business, or if something is truly exceptional about a business. All the other experiences might tell you details which might be biased. There is no real number to define if reviews can change perception about a business. Reviews might bring first time customers, but overall perception about a business differentiates the best and places which are perceived to be the best.

Try searching for desserts and look up the reviews of a places, you will be surprised how good reviews are and how many people write reviews for dessert places.