Filter are typically optional: when a user accesses a Dashboard, he or she can set a filter or not set a filter. That’s up to them.
However, you can require a user to set a filter before they can run a Dashboard. In that case, the Dashboard will look like this on first access:
If the user tries to click Run, he or she will see this message:
It’s only after the user configures the filter that the Run button becomes available:
To make a filter required, create the filter and then, in the Add/Edit Dashboard Filters dialog box, click Customize Filter and set Require a filter to run this dashboard to Yes:
Save the filter, and the Dashboard will not return data until the filter is set.