4 rounds of interviews. The last 2 were attitudinal and involved a business case presentation in front of a panel, and they took up the entire afternoon. After the 4 rounds, the hiring manager informed me that they had chosen an internal candidate for the position, despite my experience and skillset were clearly superior (I'm already performing the same role for a competitor). It seems that the extensive interview process was merely a formality, and a waste of my time.