You often see "coincidences" like this in the Corporate world. Let me be clear that I have no idea what truly happened, but here is one possibility that happens regularly:
Rising star hires an individual A many years ago and some mutual loyalty forms over the years. This individual A rises quickly to a high level, on the heels of the Rising Star, who turns into a superstar. Over time, people begin to wonder how this individual A achieved such a lofty level, as his performance doesn't seem to warrant it. Individual A seems to be a survivor of corporate changes and turmoil, despite the apparent underperformance. One day, the Superstar retires. Very shortly thereafter, individual A leaves or retires. Bottom line - the Superstar protects Individual A (either directly or indirectly) and prevents him from getting pushed out. But when Superstar leaves, the new executives quickly do what should have been done 5 years earlier.
Another common occurence is when the new executive takes charge, he brings in a few of his trusted assistants for senior positions. In this case, the reason for departure isn't necessarily underperformance - it is politics. In some cases, younger people pushed out in these circumstances will end up being hired by another company in the industry for similar positions.
To reiterate, I have NO IDEA why Mr. Bhagat is leaving. Just explaining that these departures are sometimes more than meets the eye.