What failure mode is typically preferred for in-line network taps?

In-line network taps are typically configured to fail-open since they are used to create a copy of the network traffic. Devices that provide in-line security like IPS systems may be configured to fail-closed because their failure removes critical security functionality. Fail over describes the ability to fail to another device, which is not a common function for an in-line tap. Fail-reset was made up for this question.