When you can’t add Time Dependent Action in Workflow Rule in Salesforce?

Hi,

Limitations
Time triggers don’t support minutes or seconds.
Time triggers can’t reference the following:DATE or DATETIME fields containing automatically derived functions, such as TODAY or NOW.
Formula fields that include related-object merge fields.
Salesforce limits the number of time triggers an organization can execute per hour. If an organization exceeds the limits for its Edition, Salesforce defers the execution of the additional time triggers to the next hour. For example, if an Unlimited Edition organization has 1,200 time triggers scheduled to execute between 4:00 PM and 5:00 PM, Salesforce processes 1,000 time triggers between 4:00 PM and 5:00 PM and the remaining 200 time triggers between 5:00 PM and 6:00 PM.
You can't archive a product or price book that has pending actions.
If time-based workflow actions exist in the queue, you can’t add or remove time triggers or edit trigger dates without deleting the actions first. Because the deleted records can’t be restored, carefully consider the implications of editing the workflow rules before you proceed. If you decide to edit the workflow rules, deactivate the workflow that you want to edit, edit the rules as needed, and then save your changes. For information about finding and deleting time-based workflow actions in the queue, see Monitor Pending Workflow Actions.You also can’t add or remove time triggers if:

The workflow rule is active.
The workflow rule is deactivated, but has pending actions in the queue.
The workflow rule evaluation criteria is set to Evaluate the rule when a record is: created, and every time it’s edited.
The workflow rule is included in a package.

Thanks

There is a criteria “Every time a record is created or edited” in this you can’t add Time dependent action in Workflow rule.