User blog comment:Slashingstrike/Master Yi's Wuju Style rework idea/@comment-3578129-20180617144841/@comment-15077371-20180617174054

The slow portion will allow master yi and his team for better ganks or provides escape for Yi. Now days champions put master yi into mobility creep and I think this will even the odds as he is suppose to be highly mobile champions. Without CC its very hard to gank a lane

Master Yi as a skirmisher is suppose to be a counter to tanks therefor the armor reduction can be used to amplify his damage vs armor stackers as well as pushing back the front since their armor will be shattered giving Master Yi a decent zoning tool for lategame