In order for me to get "A" I have to have 21 total accounts. Does it seem right to you? I have 3 credit cards and that's already more than enough for me. Not sure whoever in the right mind need 21 credit cards except for those transfer their credit card balance from one card to the other all the time.
The same page also shows there are 33.3percent of population owns 20+ credit card accounts. Obviously I am the outlier from their stats.