Match History Rating

Why do some games in the match history show your rating but others do not? https://imgur.com/05lABLF

The ones that don't show I got S- (Graves), (S-) Graves, (S-) Thresh, (A) Swain I thought maybe it's bugged where S- doesnt show, but nope, scrolled down a few more games and a Lux game with S- showed the rating and another game near that didnt show where it probably wouldve been like a B or C rating