What was the 750GeV debacle? That thing were some people said LHC had found a new particle maybe?
A spurious signal at LHC (that disappeared in later runs) that spurred a cottage industry of arXiv submissions trying to explain it. Authors, mostly grad students, quickly submitted hundreds of low quality articles trying to get in on the "discovery". Later articles would cite over 400 previous articles and it became one giant circle jerk. There were even blog posts complaining about the blatant "ambulance chasing".
https://motls.blogspot.com/2016/06/ambulance-chasing-is-just...
http://resonaances.blogspot.com/2016/06/game-of-thrones-750-...
arXiv does not accept papers from authors with no institutional affiliation and viXra was the only (and ugly) alternative. There is an opportunity there to fix both sites.