I highly recommend this post by Above the Law's "Anonymous Partner."
For all of the talk of disruption in the legal services market and how companies that may or may not be running afoul of unauthorized practice of law rules are eating Big Law's lunch, as Anon Partner notes, the biggest threat to BigLaw's viability is that many current BigLaw partners have different values than those who preceded them. They are generally less interested in the long-term success of their firms and are increasingly reluctant to pass on business or retire. While it is not surprising that senior partners do not want to forsake their shares of firms' profits, the reality is that low partner productivity is the main reason for Biglaw's tepid performance, as I have noted previously. With unproductive lawyers in the senior ranks, there is also less room for firms to hire lawyers who can be groomed to be future leaders.
I don't pretend that there is an easy solution to this problem, but most efforts to confront the "new normal" have little to say about the responsibilities of those who have done very well in the profession.