If a law firm represents you in several areas of law, it’s harder to evaluate the performance of the firm as a whole
As equities analysts have a harder time evaluating the stock of conglomerates, so law departments may have a harder time evaluating law firms that have provided them a range of legal services. This idea was expressed at an Ark conference in these words: “It’s harder to evaluate a firm that covers lots of matters than a more precisely targeted one.”
I have not heard of any legal department that evaluates its primary firms down to the granularity of practice areas. Legal departments, to the modest extent that they formally evaluate firms, do so at the level of the entire firm. That holistic perspective becomes less and less insightful the broader the firm’s legal services. The analogy is to client satisfaction surveys that ask about the legal department as a whole, rather than about specific lawyers or groups of lawyers. Over time, legal departments should look at their spend by practice group and try to evaluate firms at that more useful and reliable level.