Distractions, task prioritization, loss of situational awareness, or disorientation.

Bottom line

A contributing factor in many accidents is a distraction that diverts the pilot's attention from monitoring the instruments or scanning outside the aircraft. When a pilot becomes task saturated, there is no awareness of input from various sources, so decisions may be made on incomplete information and the possibility of error increases. Effective workload management ensures essential operations are accomplished by planning, prioritizing, and sequencing tasks to avoid work overload.