When a relay is turned on or off the relay has a default STATE time of 5 seconds. This 5 second minimum STATE time is built into the operation system and may not be overridden by a user.
Motorized valves often require a minimum amount of time to physically transition from open to closed. The minimum run time prevents short cycling of valves which can lead to a valve to stick or to fail.
Another way to protect equipment from short cycling is create a large enough Deadband (offset) to prevent toggling on the relay.