Bronze vs Diamond
So, in a time not that long ago, I used to play in Nightly RP tourneys. In those tourney's, the teams were always a Bronze/Silver/Gold/Platinum/Diamond vs Bronze/Silver/Gold/Platinum/Diamond. I was the Bronze on one of those teams, and more often than not, I did end up as ADC vs [Surprise] a Diamond. This did happen often, but it wasn't quite the stompfest you'd expect. Both supports were typically Silver/Golds, so, their skill level was fairly equal. The ADC's were different, but not that much. More often than not, I would WIN the lane, with a higher K/D, higher CS, and overall just being the better player. During these tourneys, I realized that the difference between Bronzes and Diamonds was Mid/Late game play. While I would dominate a lane and overall have an exceptional game, I would be unable to handle the way that the enemy ADC would rotate, and I would end up being down by 50-100 CS at the end of the game, while being up 25-50 CS at the end of lane. Tl;dr: If you're a Bronze/Silver player, you (I'm included in this, as I make this mistake) need to focus more on CS'ing and making great map play during the Mid/Late game, rather than going dukes up all the time and trying to force fights.
Edits: 1. I'm not saying that Bronzes are on the level of Diamonds, I'm saying that low elo has difficulty doing anything past the lane phase because they are constantly out thought and out maneuvered 2. I have an example. While it was a win, I still did struggle coming out of lane phase because I was making key mistakes that led to some fairly serious deaths that I had to deal with. http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/1985592105/42084383?tab=overview The Trist and Ekko are both low diamond.