I'm by no means going to pretend I'm amazing at this game or anything, because I'm honestly pretty bad and have mainly been playing bots. That being said, lots of games like league are going to have games where you simply lose due to the way the game plays out. When I play games like Hearthstone or something, there are simply some strategies that nearly always beat my Priest deck. It's just the way video games that aren't entirely skill based are.
Maybe if you snowballed harder earlier, your jungler ganked you more, or your mid roamed top the game would have been played out differently. Maybe this would have happened if people didn't focus attention on mid and bot as much.
However, just remember that for every game like this, you probably have a few that "go the way they are supposed to" with the early game champs getting an early lead. It typically feels like these situations happen more often than they actually do because they are so frustrating, that's simple psychology. You never remember the game that played out the way you expected to from champ select. This doesn't necessarily mean things need to be changed.
Just my opinion though. I main Jungle and ADC.
