In Azure Active Directory (AAD), you can set groups to expire by configuring group expiration policies. Group expiration allows you to set a predefined time period after which a group will automatically expire and be deleted.

To set groups to expire in AAD, follow these steps:

1. Sign in to the Azure Active Directory (aad.portal.azure.com) using your administrator account.
2. Under the Manage section, select Groups.
3. In the group’s settings page, click on Expiration.
4. Set the expiration period by selecting a number from the dropdown menu or custom
5. Configure a notification to alert groups with no owners before the expiration.
6. Save your changes.

Setting groups to expire in AAD has several benefits:

1. Group lifecycle management: Expiring groups ensure that outdated or unused groups are automatically removed from the directory, reducing clutter and improving overall group management.
2. Security and access control: By setting an expiration period, you can enforce periodic reviews of group memberships and access permissions, helping to ensure that only authorized individuals have access to resources.
3. Compliance and governance: Expiring groups can help organizations meet compliance requirements by regularly reviewing and validating group memberships, and ensuring proper access controls are in place.
4. Cost optimization: Removing expired groups helps reduce unnecessary licensing costs associated with unused groups.

By configuring group expiration policies in AAD, you can automate the process of managing group lifecycles, improve security and compliance, and optimize costs within your organization.