Lots of big languages are successful; C++ is a prime example. My understanding of Lisp 'history' is that most CL implementations were by large vendors charging

Lots of big languages are successful; C++ is a prime example. My understanding of Lisp 'history' is that most CL implementations were by large vendors charging silly licensing fees and they got undercut by C and Pascal vendors... Another theory I have is that Lisp encourages the use of macros which makes sharing code more difficult. Or maybe it's simply that the languages that built/were built on Unix and PCs became most popular as those systems were most popular (C, C++, Perl, Python, Ruby, etc...). And of course now the language of the browser (JS). Or maybe a bit of everything. On the plus side, SBCL is pretty fantastic and people still do things with Lisp.