Havick raises an interesting point. The word being TASKED. This word brings subtle, but not inconsiderable pressures of their own.
Ive regularly had to ferry aircraft at short notice for maintenance, often at the end of the day. "it has to be there" being the implication. Either the a/c is not IFr or I'm not current, an hr of daylight left when the boss pops in and says get the aircraft down to maintenance pronto. Murphies law dictates the wx will be marginal too. Not NVFR able The pressure is on, you feel it intensely.
A few times, I've had to stand my ground and say no. Much to the boss displeasure. If there is a flight where you will make a cockup, this is it. A few times after take off, I have said to myself WTF am I doing.
I can image the pilot, would have felt the same pressure. 4pm at EN, low wx, EoD 6ish and ETA very close to EoD. Low cloud, rising terrain, NVFR. The pressure of getting a not well pax home. In this scenario, there is zero margin for error. Even the most experianced pilots can fall victim of this subtle build up of pressures.
Unfortunately, on this instance all the holes in the cheese lined up.