Brock Lesnar returned to WWE the night after WrestleMania 28 in 2012. Upon his arrival, he was immediately thrusted into a feud with John Cena. Intrigue in WWE started to flourish and the momentum coming out of WrestleMania 28 was in full-swing. "The Brock Lesnar Experiment" was off to the races. WWE knew that they could bring back The Rock on a part-time basis and fans would be interested. Would the same be said for Brock Lesnar? The majority of wrestling fans didn't know what was in store for Lesnar's WWE run...and we really still don't. He seems to come and go as he pleases and never sticks around long enough to make a difference. Brock has been put in position to be the one man to defeat The Undertaker at WrestleMania and even won the WWE Championship in the most dominant fashion of all time. However, unlike other part-time WWE superstars, Chris Jericho & Rob Van Dam, Brock Lesnar is never around long enough to truly make his presence known. He doesn't wrestle on Raw, Smackdown or house shows and seems to be held above other WWE superstars on the food chain. As of this writing, "The Brock Lesnar Experiment" seems to have failed, even though there is still time to save it. WWE Network subscriptions haven't skyrocketed, ratings are stagnant & overall interest in the product seems to be waning. Here are 10 Reasons why WWE's Brock Lesnar Experiment has failed up to this point.