With the current Dynamics 365 (Online) feature, once a record such as a phone or appointment in the [Activity] entity is changed to Complete, customers cannot return it to the Open state by the normal feature .
Customers must create the workflows one for each entity in the [Activity] entity to change the state of the record, resulting in the customers spending business resources to creating them .
Therefore, it is considered that the efficiency of business can be improved if the record status can be changed by the normal function like other entities without creating the workflows.