Everyone should learn to play a few non-damage supports well.
Everyone wants games where they are fed and hard carrying. Those are the best, and most enjoyable games to play. But sometimes we need to let others do the "carrying" and take a more defensive/ utility role. Sure every champion that is far ahead and fed will be able to hard carry any game. But not every member needs to be fed to win a game. Simply because, where if a Riven were to not be fed (hard to imagine but it happens) then she is more useless than any non-damage support. This is because of the kits each champion has. Non-damage carry supports are designed to be useful even if 0-20. Carries are not. They are feast or famine.
The point is that, playing non-damage support has one of those unique qualities where even if you are -20 kda, you still are going to have a large impact on the game. So instead of trying to win the hard way by playing only carries, take a few wins as a support. they are much easier to get. You also get to have a far lower queue timer as a perk, and more games = more wins.
If you still are not convinced, let me give you an example. As a Blitzcrank, you have 1 job. Land a Q. Now lets say that for the first 20 minutes you miss every single one. Best part about that kind of situation is that you still are seen as a threat, even though you have done shit to prove you actually are. Back to the example, it is not going well for you. However your team is doing alright, nothing great but nothing bad. And at 21 minutes you are in a team fight and you land your first Q. Well you basically executed that player you grabbed, and your team wins a major team fight because of it. Best part is, that was the first one you landed all game, but for the entire game after that, you will have enemies run in fear at the sight of you because of it.
Champions like 
who have these game changing abilities are will make for some of the easiest games you will ever win. Yeah their Lux is 14-2, but one hook from a 0-7 Blitzcrank into the full team equals a shutdown (and most likely salty) Lux, or at least a blown summoner spell or 2 for her escape, for essentially a small amount of mana and a few short ability CDs as a cost.
with a silver or lower ADC, guess what: they won't follow up about 50% of the time and farm when I go in. I don't even play that aggressive as 
) because a non-response to picks was very frequent. The other thing players didn't understand was WHEN to go in. So I often has two scenarios with bad adcs: they would passively farm when their was an opportunity for a pick or there was no opportunity for a pick and they would just be straight aggro the whole laning phase.
for two years. Now, I never play support anymore and I'm actually climbing the ladder by playing top and mid lane. Let's say I got randomed into support, I would just play either 
. Since I'm a solo player, and had felt like random ADC's would just let me down, I need to be capable of carrying the game.
and 
and this champ works well for me. 58% winrate out of ~65 games. At the same time I really try to pick some utility champions like 
even 
, but with exception of Sona, I fall short. Negative winrates speak for themselves.