When looking to use a module from the Drupal community there are a number of factors to consider, beyond its functional use, that determine suitable quality and support for your organisation to use.
When you deploy a Drupal site into production, who is responsible for maintaining it? How long will that site live for? These types of questions shape the risk tolerances of the project. E.g. Lower Drupal competencies means you need greater community support and more stable modules.
All modules on Drupal.org are open source and fall under the GPLv2 open source license. They are free to download and use at your own risk. Each project has its own set of maintainers and a sub-community that uses the module, interacts through issues and contributes bug fixes and feature enhancements.