If you are average player , ranked is a big big lottery.
Of course challenger can smurf to diamond easy , but say you are gold 5 with real skill level of low-mid platinum.
You may never reach ur true elo , or it could take eternity because of afk/troll/unskilled/brainless/feeders. Higher the elo harder to carry.
Also one thing that annoys me is that too many people dont take ranked seriously , (trying new champs on ranked etc..) and when they feed they say cmon ita just a game..yes it is , but ranked is ***** competative , go play normals of u dont care about rank. I will probably quit lol (I know nobody cares lol) because for me its getting more stresfull than fun.