He talking about dou queue players. That means there are 2 people trolling not just 1. There is a reason leavebuster exist you know. You not being there decreases your teams power and the amount depends on what role your playing.
Ex.
ADC- sustain damage gone
APC- majority of your magic damage and their powerful cc (depends) gone
Tank- one member of your frontline (the position next to support that doesn't get enough credit) and their powerful cc gone
Fighter- one member of your frontline and their powerful cc gone
Assassin- burst ad or ap damage gone
Jungler(the position blamed for the consequences of others)- no pressure to enemy laners and enemy jungle gets free farm and buffs
Support- majority of your wards (sightstone saves tons of gold when it comes to wards) and probably a good amount of your utility gone
Its very hard to play with a positive attitude when someone important (and every role is important) trolls or goes afk. Especially if your playing in lower tiers of ranked.
Don't believe me, then go on YouTube and watch videos on how to get out of bronze. All of them will say that the team with the most or more powerful cc wins. Most of my ranked matches this season is just me getting out of bronze. To top it off, lower ranked players (and I know since I'm kinda still one of them) are more likely to make (but not on purpose) the same mistakes more then a few times before they realize what they're doing is wrong.
P.S. Remember to ward kids and spin-to-win
mid and a duo q bot dosnt want to surrender when they fed the hell out of theyre lane, the game is not fun. if the 2 people wo are the most ahead plus the majority want to surrender could the surrender just work. note if your the carry you can still reject the surrender.
when you're 
=/
