This is true most of the time but you can “hold” your % rank even if you lose a match, as long as you do good enough. Normally more common on an odd loss here or there, you don’t always have to go down, just to clarify
I lost 3 Koth matches consecutively at 97.30% Onyx 3 and did not move at all. I was out of the ballpark MVP on each of these matches because they were much lower ranked players. I won a match after these 3 and moved to 99.60% Onyx 3 as MVP. I lost 2 matches after this and did not move.
The next match we won and as MVP I moved to D1 83%. (Hell, I can’t even remember if I was MVP on that last match…)
^This is what keeps you from losing % when you take a loss. If you have a background track record of meeting or exceeding expectations in performance and then you take a loss or multiple losses (while still surpassing expectations) it shouldn’t really affect you in the long run or dock you for it.
This was last night, right? If so, I was MVP in the match you moved up to Diamond. The match before I couldn’t buy any success with that lag but you tore them up despite our loss.