People often assume that Yahoo! moving Viaweb off of Lisp, and Sony moving Naughty Dog off of Lisp, says something bad about Lisp itself. Bill Clementson looks at the same data and comes to the conclusion that lisp is good for startups (emphasis mine):

So, Yahoo acquires Viaweb and rewrites it. The end result is inferior to the original Lisp-based product. Sony acquires Naughty Dog and decides to eliminate the Lisp-based development infrastructure. The end result is an inferior game development environment. Sure, there were probably a lot of reasons for these decisions by Yahoo and Sony… however, the end result for both companies has been something inferior to what they originally acquired.

But, for both Paul Graham and Naughty Dog, the use of Lisp allowed them to develop products that pushed them to the front of the pack. They were subsequently bought out; however, the fact that their Lisp tools were subsequently discarded does not throw a negative shadow on Lisp. Lisp got them to where they needed to be to succeed — definitely a quality that entrepreneurs want in a programming language!