Silver/Gold players are not that mechanically bad though. They can aim skillshots and time their abilities pretty well. It's just not stopping to think before doing, or not having an idea on what to do in certain scenarios. An example, some days ago a Silver 1 friend was playing irelia, he had his Q and was about to kill an enemy, instead of waiting for the enemy to flash over the wall (that's what he did) he used it as soon as it got off cooldown.
For me, the easiest way to win matches in low elo is letting the enemy push and push and push, then you have your whole lane to outplay your opponent or you can also get ganked. Get ganked, get fed, carry.
Apart from that it makes the enemy want to dive you, which always ends up in at least one kill for the one that is being dove.