My personal thought on the why it isn't popular is the fact Common Lisp has multiple implementations. Which one do I pick? What are the differences? What's the

My personal thought on the why it isn't popular is the fact Common Lisp has multiple implementations. Which one do I pick? What are the differences? What's the compatibility like should I decide to switch to another implementation? Experienced common lisp users will know the answer but try and get a manager or leader with no experience to spend time trying to understand/read about all these things when simpler/easier choices that work the traditional way exist. This can apply to scheme to some extent as well.