I want to ask a theoretical question.
For example, there is a project on Drupal 8. Working on the project, developers find a php library on the GitHub, include it via Composer and use it in their modules.
They don't create drupal 8 module which would present the library and contain files of the library, copied from GitHub before. And to use the library it would be necessary to install the module.
Is it the correct way to attach an external php library via composer and afterwards use it without creating a module for Drupal 8 for this library ?