From: Street Fighter and Guilty Gear… somewhat
Genre: Video Games
Who said it?: Ricki Ortiz and various announcers/commentators
The story behind the quote: While this quote doesn’t come directly from a video game per se, it is video game adjacent and actually is very important.
The quote actually has two origins in a sense. The first time the quote was uttered was during a Street Fighter IV match between Ricki Ortiz and Wolfkrone. Wolfkrone’s C. Viper managed to perform a clutch Ultra combo on Ricki Ortiz’s Rufus. Wolfkrone thought he won and stood up to raise his hands in victory. However, he was wrong and Ricki managed to come back to steal the victory. In a fit of hype, Ricki exclaimed the quote and UltraDavid, one of the commentators for the match mirrored Ricki’s statement. This was the actual birth of the quote.
However, the quote only really gained notoriety during EVO 2015’s winners semi-finals for Guilty Gear Xrd. In a do-or-die situation, Woshige managed to win the second round against Ogawa to stay alive in the tournament. However, he apparently forgot he needed to win two rounds because Woshige prematurely left his controller to celebrate. This didn’t matter to Ogawa as he immediately pummeled his opponent’s helpless character to move on in the tournament, all the while the commentators echoed Ricki and UltraDavid’s words…
Geek wisdom: Don’t count your chickens before they’re hatched. Sometimes you can prematurely celebrate “a sure thing” but there are going to be times when these “sure things” actually don’t push through. It’s better to actually celebrate after achieving your goals rather than do it before it actually happens.
My Geek Wisdom 
I’m waiting for the “Kept you waiting huh?!” epic quote from Snake in Metal Gear Franchise :))