Seldom
But only a major cock up if the aircraft was fully servicable or the weather was as has been suggested at the time of the crash.
An aircraft does not have to be fully serviceable to be perfectly safe if flown within it's limitations. A good dose of looking at the A700 and application of nervousness brought on by the rumour/experience mill would be a good starting point for the days task.
At the end of the day these two pilots flew this aircraft into a rock - indisputably. I believe that the aircraft shortcomings - all indisputably unproven by all the posts above - are a sideline to the lack of planning and airmanship shown on the day.