Some people seem to not be aware, but there are groups that focus on certain games/type of games to negative review bomb, some with even hundreds or thousands of users.
Here's a Kotaku article written on it a year ago:
http://steamed.kotaku.com/steam-review-bombing-is-a-problem-1701088582
But if you look around you can see it happen in a number of places. These groups include people who take some kind of vendetta upon something, be it a group of GamerGaters, people who hate microtransactions in any way, shape, or form, people who go on a vendetta against certain genre of games that have popular 'shitty' entries from developers (but effect even those games that are actually good), etc. Some are just voices wanting to be heard, some are this weird growing circle of 'video game hate groups', that have found a place recently.
There's also the opposite and some shitty developers will pay to get positive review bombed on their game to try to create the illusion that it's good. That happens less, but it most certainly has happened.
I'm not suggesting anything be done about it since this is the unfortunate effect of giving anyone a platform to be a voice, putting needless restrictions on the system would either hurt legitimate customers and probably not effect the groups anyway. Again, I think the best thing to do is just raise awareness.
The times it's most obvious is when there's a page that's mostly positive reviews but people have gone out of their way to thumbs down all the positive reviews and thumbs up all the negative ones.
