I went to the bottom of pinside's top list and found the 16 lowest ranked mainstream games (no boutique or special order games). This is round four of this poll, with 2 games remaining. I'm bummed that AMH beat out The Avengers. It is, IMHO, the worst mainstream machine of the last decade.
Round one can be found here: https://pinside.com/pinball/forum/topic/worst-pinball-machine-in-the-last-decade
Round two can be found here: https://pinside.com/pinball/forum/topic/worst-pinball-machine-in-the-last-decade-part-ii
Round three can be found here: https://pinside.com/pinball/forum/topic/worst-pinball-machine-in-the-last-decade-semifinal
Remember that you are voting for the worst game, the one that sucks more than the other.
Overall, I expected it to be WWE vs. Avengers. Rob Zombie was a surprise and almost made it to the finals (by two votes). Mic on a stick was a surprise as well; I thought it would have dropped out earlier. Anyway, It's been a fun poll!