MUMBAI, Sept. 18 -- A way of functioning seen as defiant by the BCCI, disagreements over selection, players expressing their dissatisfaction with the captain's way of doing things, the World Test Championship defeat, R Ashwin's omission from the fourth Oval Test against England, and the cancellation of the fifth and final Test in Manchester - each of these factors played a role in Virat Kohli announcing that he will step down from T20 captaincy after the upcoming World Cup, according to people aware of the matter....