Organization playbooks as the role give more reliability and reusability to any plays while considering a task where MySQL installation should be done after the removal of Oracle DB. You need another requirement to install MySQL after java installation. In both cases, you need to install MySQL, but without roles, it needs to write playbooks separately for both use cases. Still, once using roles, the MySQL installation role is created can be utilized any number of times by invoking using logic in site.yaml.