well, unfortunately custom games are where trolling and random things are supposed to happen. Normals are for simply playing the game and trying to win
ranked is for playing the game to win
I was playing as a karthus support (yes, I consider it a thing because of the amazing poke damage for almost no mana)...my kogmaw partner rushed trinity force...I did more damage than him and went 0/12 compared to 3/2, but we couldn't stop our vayne opponent with their jungler nautilus constantly camping us because Kogmaw literally did no damage in comparison to them
it wasn't a fun match, especially with all the disconnects happening to me...combine that with a carry doing no damage and it's no fun...would rather play soraka...at least she can crowd control...if only barely