The sumo deadlift from deficit develops great levels of hip strength. Strong hips usually mean big numbers in primary lifts such as squats, power cleans, snatches, and deadlifts, not to mention help make an impression in your Thursday night Zumba class.
The sumo deadlift from deficit isn't discussed nearly enough as a tool used to increase strength in other lifts. Standing on plates increases the range of motion and makes the hip extensors work even harder.