How is Kemba Walker to Small to play in the NBA?

he's listed 6' on nbadraft, so he could potentially be a max of 5'11, though some players get away with it with bigger shoe sizes and get another 1-2 inches added to their listed height. but, there could be other factors that analysts and writers mention when stating his small size such as his weight; he's around 170?.. so he'll need to add a bit of weight in my opinion. also, other factors to consider are his bulk and muscles and reach/armsize etc. which in this case under average compared to most nba players playign the point guard/shooting guard position.