I wish people would stop thinking it's 100% okay to lose
This idea that because you are not in a ranked game, then you have little to no reason to feel any bit of remorse for losing. I'm sick of people saying that it's essentially okay to "Get poor grades on homework assignments and only pass the Final Exam"-- as if that turns into a final grade that looks "good".
I just came back from two games in a row where my team lacked a player because they either couldn't connect or possibly decide to not play when they could have suddenly thought that they were bored enough. And someone on the enemy team says, "It's just nexus blitz, you shouldn't be salty". You can look at my match history and see a good number of losses but they're not from something like a player that doesn't play at all. I shouldn't have to load up a game that has what may seem like a 20% chance of failing. Nobody should be going into a match and hoping that all players will be active in that match.
And it may be just two "unlucky" games in a row, but as soon as it happens once, it can happen again, and it could happen again after that.
UPDATE: 3rd game in a row it happens and you're not convincing me. Saying that it's a "video game" isn't quite enough considering that it's something we supported for at least 8 years. And apparently you guys assumed I'm unable to distinguish games from reality.