In any major aviation accident there is never one thing that causes it. There is a series of events that come together and create a tragic end.

Some possible factors:
Crew workload just prior to accident.
As a CR2 FO, I can attest that during a short taxi out on a first flight of the day your workload is higher than usual as you have more checks to do.

Tower workload:
Was there only one controller on-duty at the time of the accident?

Wx:

Airport Facility:
Were the rwy lights on the short rwy on or off at the tx

The ultimate question for the NTSB is why did this experienced crew attempt to t/o from the wrong rwy and why the tower controller didn’t warn the crew of the error prior to issuing t/o clearance.