Lawyers who work for corporations object to convergence programs for many reasons. The ones I have heard include the following, listed roughly in order of their significance.
1. Geographic dispersion of our matters means we need firms admitted in many states and familiar with many courts
2. Complacency on the part of law firms once they are selected to the small group
3. We don’t get the best ideas on service delivery when firms are nestled on our short list
4. Loss of legal substantive expertise since no single firm has the best legal talent in very many or any of the specialty areas where we may need it
5. Disappointment on the dollars saved by the law department
6. It is risky to put all our eggs in one basket
7. Convergence programs consume huge amounts of time to structure and monitor
8. Less comparative data becomes available about law firm performance and cost
9. It will disappoint internal clients who have come to like incumbent law firms
10. Conflicts of interest worsen because more work must go to fewer, (probably) larger firms
11. Finance and procurement likes it so it must be bad for us
12. The number of golf rounds, lunches, and other freebies diminishes