Using the drupal console I created a module in a /sites
subdirectory - because I want that module to be available only during development.
The creation process worked.
I tried to create a controller using the console and it said there was no such module. I tried enabling the module: no such module. Using:
drupal debug:module --type=no-core
listed the one other module I've created which is in /modules
.
(Yes, I cleared caches.)