I was just looking through your match history to find both games, and I could only find the Azir game, I guess the Xin game is too old. But looking at it, it looks like you got most of your kills right at the end after you had been spoon fed by the Warwick, and the system will pick up on that. The Xayah and Warwick got first blood. You did the most damage by far, but my guess is that came in when you got the quadra kill at the inhib. Your CS is really low for an Azir at 30 minutes (You should aim for over 200). You did well, but compared to other Azir players in the same lane, your CS was low, you only placed 1 ward the whole game, and the Warwick out performed you. My guess is that to the system in place to check that stuff, it seemed like you were spoon fed by the WW and then came in at the end to close it out. An S worthy performance would mean you were dominant the whole game, or superbly dominant at the end of the game. Don't get me wrong, you played very well it seems. You had a high score and what not, but I think the wards and CS are what killed it.