Two actually, changing the position of the final way point and not telling the crew.
and descending below MSA, to 1500ft, at 260kts, in an area you have never been to before, with met conditions that prompt you to say “actually it doesn’t look very good up here”, after being told that the conditions for sightseeing were unsuitable, and without getting the radar ID and let down that was in the pipeline.
If we combine all of those factors, we get a picture of why the accident happened, if we decide to ignore either the company mistakes, or the pilot mistakes, we get an inaccurate picture of why the crash happened.