ISB is preferred by students having higher work-ex as their unique one year course help them save on opportunity cost. Apart from this they have foreign collaboration. Its a coincidence that work-ex and foreign collaborations are cited as the most important parameters for these ranking, which has helped ISB to score better.
Its good that these people have acknowledged that some of the big B-schools have not participated in their ranking system. But, what good is a ranking system where 4 out of top 10 schools have not participated. And, can't these people see that whatever method they have used to arrive at the ranking of non-participating B-schools is obviously wrong. So what good are these rankings.