The Worst Part About Bronze

is hands down the objective control. Very rarely should you just abandon a tower, refuse to contest a drag/baron, etc. And after you win a great team fight where you ace them is not the time to back. You take drag/some towers, and back as they get back to lanes. And with the mid focused meta, all you have to do is start a monster wave and let minions take the sidelanes. If you give up all of these things, even if you start out winning a game, you will ultimately lose as they get global gold and buffs, which will turn into less item deficits, which will lead to them winning team fights.