Apparently, the quickdraws used to equip the route were slung incorrectly, which resulted in total failure and a groundfall. Details regarding the improper usage of the quickdraws are still vague, however, a rough translation of Grimper's report notes that the slings on the draws were attached to the carabiners incorrectly. The report indicates that the slings were improperly attached to the plastic/rubber device used to keep the carabiners from turning on the slings. Therefore these mechanisms were the only attachment between the sling and the carabiner and are apparently what failed as they are not intended to hold a fall.
Although four correctly strung quickdraws were on the route, these quickdraws were unfortunately placed too low to save Traversa. Traversa was airlifted to Grenoble, France, after the accident where he was hospitalised. He died today, after fighting for his life for three days.
Traversa was a young climbing phenomenon from Ivrea, Italy. He climbed his first 8b+ at the age of 10 by sending Sarsifal in Tetto di Sarre, Italy. Just two days before his accident, Traversa climbed his fourth 8b+ - Pablo diretta in Gravere, France.
We don't know exactly what happened in this case, but several years ago, and unrelated to this accident, we made a UKC video highlighting how easy it is to incorrectly clip some quickdraws. You can see this below.
VIDEO: The Potential Danger of Open Slings
Again, please note this video was made around 4 years ago, and not in response to this accident. However we feel it may be relevent, and is worth highlighting again.