Freeze User #inSalesforce

Suppose you are not ready to deactivate a user but want to restrict the user from log in to Salesforce, then use this.

In cases like - when a user is selected in a custom hierarchy field.

Freeze can be used for a temporary period before the deactivating, while you are transferring user records etc. or while activities before deactivation of user is in progress.

Steps:

Setup | Users | Click the username of the account you want to freeze | Click Freeze to block access to the account or Unfreeze to allow access to the account again

Freezing user accounts doesn’t make their user licenses available for use in your organization. 

Reference: https://help.salesforce.com/s/articleView?id=sf.users_freeze.htm&type=5