In design any SaaS product, it's important to create enough transparency between the business client, and their users. For a management product, (such as a sports club management), first time that users come in contact with a club is when they are being added by a manager to the system.  For many reasons, mainly privacy issues, it's important that users are notified, when they are being added to a system. This can happen in two scenarios: 1) When system administrator adds someone to the system for the first time, and 2) when system administrator adds an existing user (back) to the system.  

Here's an example of the second scenario for a system with possibility of adding family members (who share a single email) to the members list.