I'll just add something to this as well.
I find a lot of the bronze and silver players, and gold also suffer from some type of self entitlement. I have some friends that play and take the game very seriously, however have been stuck in bronze and silver for 2 seasons now. When you play League, you need to reflect on every game and learn something. You can't constantly pass the blame to someone else and say you lost because of them. My friends are CONSTANTLY doing this, and when I try to point out mistakes in their game when I spectate they get extremely offensive, and it actually makes a rift between our friendship....which to me is crazy. They want me to carry some of them to Plat, but I keep tellin them that
A) They won't learn anything that way.
B) They are going to seriously get rekt and get even more angry.
C) They are goin to tank other peoples games, and again.... pass the blame and eventually get demoted.
You need to be constantly learning in League. Just because you play 5 hours a day, doesn't mean you are good. I recently got my girlfriend into League, and after 2 weeks I was wondering if she was going to stick with it, as she was getting frustrated. However, she is a very smart girl, and at only Level 23, she is playing a support role better than half of the people I have seen in Gold and Platinum. Reflect on your matches. If you screw up, accept that.
The other thing I see a lot of players do is follow the flowchart. ALWAYS look at your what your opponent is buying, and do your best to counter build, ESPECIALLY if you have the gold lead. You will constantly make them obsolete while they continue to play catch up.
You can't control the AFKer's, ragers, or toxic people, but you can control how well you can do in the game to some degree. Carrying games are possible. Although it wasn't ranked, I played Urgot last week because he was free. First time ADC Urgot, and we won even though our Lee Sin dis-connected at the 7 min mark. How did we win? Teamwork and a positive attitude.