Here is an example where if a hop step would be executed, the save would be much more efficient and it would create less of a chance of a rebound popping back to the shooter:
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Watch from around 25 seconds to around 1:50. If you notice that when he T-pushes over he isnt always set as he is still, as he is still gliding forward. This can cause sloppy gloves or give a juicy rebound out to the shooter where it'll be easy for him to bury because you will have slid way out of position and have no moment to stay with him. A hop step would assure that you are set and your gloves will be set to make the save. Also it will eliminate the oversliding so any rebound you give out , you will be able to stay with the shooter since you arent in the middle of sliding outwards.