HDFC Bank Chairman Atanu Chakraborty's abrupt resignation was likely caused by personal and personnel issues he had with CEO Sashidhar Jagadishan and executive board members, Moneycontrol reported. Chakraborty's differences with the board became irreconcilable by late-Tuesday evening. Chakraborty was also reluctant about Jagadishan's reappointment without a performance review of his second term.