One common observation in the list of the companies is that most of them belonged to the kind of business in which the businessenvironment changes suddenly ( moat of the company is not sustainable , the company at first looked a niche and emerging one but things changed very rapidly ). Such things are common with IT telecom and sofware based companies as in thecompetitive age moats gen last for few years only . So how bright the management be themediocre business catches up very soon .
Another part looks like the shady govt and political linked business which have over a period of time proved bad for the minority shareholder like irb infra , anant raj industries ,r com , unitech…list goes on