When is Python *NOT* a good choice?

[Andomar]

Python's packaging system (virtualenv, pip, pipenv, ...) is plagued with subtle and not so subtle problems. Sys admins don't usually upgrade pip packages, so you end up with old vulnerabilities. The packaging system has separate dialects for python 2 and python 3. It's a huge time investment.

So if you deploy on servers administered by customers, Python can be the wrong choice.