This doesn't work well when
1. the low reviews are fake
2. accurate low reviews are suppressed from public view
I recently noticed several of my 1 star reviews on Google maps and Amazon are only view-able to me. If you login using any other account they aren't seen. I've read their policies and cannot identify any violation. I've attempted to contact google through their community feedback forum to understand what I said that prompted the suppression. So far no one has been able to provide any reason for the suppression nor any suggestions to have the suppression removed. Nearly two months later I'm only told 'they' are waiting for an official response from google.
Considering my reviews are based solely on my experience with the product or service and are fully accurate, I have lost a lot of faith in these reviews. I especially no longer believe the Google Reviews because that is where I'm seeing most of my low reviews are suppressed. Also, the Google reviews often are much higher than reviews on other sites - this is especially true for contractors.
Further, if you do some basic searches, you will find plenty of sites that instruct businesses how to have negative reviews suppressed. Seems like its too easy to game these - especially the google reviews.