Airplane or crew fatigue
AirAsia said Captain Iriyanto had logged a total of 20,537 flying hours, of which 6,053 flying hours were logged during his tenure with AirAsia, while the copilot, French national Remi Emmanual Plesel, had 2,247 hours.
Error in judgment for this crews should considered nil however a friend suggested me to notice that "One thing that nobody has mentioned yet is that this happened at 5:30 am which means that this crew would have woken up at 2-3 am. What was their roster like vs fatigue?"