Pet Peeves

Two biggest pet peeves in League of Legends(Not counting feeders, trolls, and AFKers):

1. Forcing Teamfights when you shouldn't.

Ex. Enemy team is Malphite, Yasuo, Orianna, Brand, Amumu, Miss Fortune, etc. Your team is Gangplank, Jax, Master Yi, Tryndamere, Vayne, Tristana, etc. Why is it every game that I have a team full of split pushers and duelists that they always want to run mid, force a 5v5, and get wombod to death? And of course if I decide to split push top and get a free tower while the rest of my team is under their tower 4v5, they will either force a fight or get caught out and then blame me.

2. Forcing baron when you shouldn't.

Ex. Your team has 3 open inhibitors. All lanes are pushing towards you. You have no wards on map, nor do you see the enemy team. Why the hell do so many people try to baron at this point? If your team is aced or almost aced at this point, you instantly lose the game.
Or even better: The enemy team has 3 open inhibs and you just aced or almost aced them. Why baron here when you can just end? Or even if you can't, you can get all 3 inhibitors and even nexus towers and then just take baron for free while they frantically waveclear around nexus?

I'm only a Gold league player, but I can attribute pretty much every loss(not counting feeders and afkers) to one of these bad decisions. How is this stuff not common sense? How do you guys deal with teams who insist on making these mistakes besides spamming pings or writing an essay explaining why it's a bad decision?

Honorable Mentions:

1. Junglers with full HP farming krugs/raptors/gromp/scuttle right next to you who do nothing while you get dived 1v1 and the enemy laner casually walks away with 1HP.
2. Junglers who don't ping their intentions or which way there are going when they gank for you.
3. Junglers on your team who are super fed who suicide trying to steal a non-significant dragon without flash(or even smite) ensuring that you lose the next teamfight 4v5.
4. Junglers who don't gank the 1HP enemy laner who is pushed to your tower without flash or wards.
5. ADCs who don't stutterstep, kite, or fit autos in between pretty much everything they do.
6. Supports who don't ward or peel.
7. People who ignore MIA or danger pings.
8. People who don't ping, don't follow their opposing laner`s roam, or don't push the wave/take the tower.
9. People who wander around the jungle for no reason instead of pushing lanes.
10. People who continue to wander around unwarded areas when the whole enemy team is MIA.
11. People who suicide dive an Anivia, Zac, Aatrox, Zilean, Tryndamere, Lissandra, Vladmir, or pretty much anyone with Zhonya`s or invulnerability.
12. People who stop pressuring other lanes while you are trying to split push.
13. People who are 0/10 but play like they are 10/0.

I may not have the best mechanics(mostly because I play from Japan with 215 ping), but I feel like anyone who wants to get better should learn these simple things they shouldn't do. That and practice CS.