Hi,
reviews have a few contributing factors:
1) all companies \ brand wish to “control” the top search results. we want the “top results” to show a good reliable successful company
2) people tend to trust word of mouth - reviews show the potential buyer why the should choose us.
3) if the product is new (to you) and you fear you are the first one to test the water; seeing other peoples comment assures you you are not the “guinea pig”.

bottom line:
find me -> trust me -> hire me (or buy from me)