Well, as it turns out:

Over two decades ago, Wiener (1989) described the concept of ‘automation surprise’, where the reaction of flight crews to the unexpected actions of an automated aircraft system was, at times; ‘What is it doing? Why did it do that? What will it do next?’ (Sarter and Woods, 1995; Sarter, 2008). Aviation safety occurrence reports worldwide indicate that such problems still occur in air transport aircraft today.
– Go-around event – Melbourne Airport, Victoria – 21 July 2007 – VH-VQT, Airbus Industrie A320-232

(my emphasis).

Sure JetStar offers cheap flights.  But they’re cheap for a reason.