Former Google employee, Ron Garret, wrote a fascinating article describing the rise and rise of Lisp in his life but the reasons why Lisp failed to make serious inroads at Google in the early 2000s.
"My colleagues were using C (K&R in those days) or Pascal. C++, Perl, Java, Python, etc. didn't exist. When all those modern languages are out of the picture, Lisp rocks. I mean it just blows everything else clean out of the water. With a secret weapon like Lisp in my arsenal in 1986 I could blow my competition out of the water with one hand tied behind my back and holding a martini in the other." - Ron Garret, Google.
Peter Norvig of Google referred to Ron Garret's statements in a recent Reddit video interview.