Instead of purchasing software to install, or additional hardware to support it, customers subscribe to a SaaS offering. Generally, they pay for this service on a monthly basis using Stripe. Transitioning costs to a recurring operating expense allows many businesses to exercise better and more predictable budgeting. Users can also terminate SaaS offerings at any time to stop those recurring costs.
Creation of organizations from the admin section is intended to be used for payments you receive from other sources or if the user don't want to use subscriptions.
Subscriptions allow you to charge an Organization on a recurring basis. So the organization will be charged at the end of the specified period for the plan they choose. You can change the subscription plan for any organization, or cancel the subscription entirely.