why are some players so mean?

you know what I mean. swears at teammates. pings 10 times for one thing. sore loser....picture my recent game. (the bad guy....) VS people like and someother person....the enemy team doesn't matter on this one! it's all on ....our story begins with a very casual game of casual draft pick. >>>>I say draven has nice name he say thanks or something>>I typed everything but I accidently tabbed out.>>TWENTY MINUTES IN! one turret is down. draven already says its gg. I am mildly annoyed>> I die from mid kled AS STUNNING HIM DOESNT STOP HIS ANNOYING HOOK! why is that? 'why' being our key word here. later draven calls our jungler garbage(I wouldn't say she was good but she helped. prolly autopicked for jg.) calling her a noob,casual and told everyone to report her for AFK. zed is 0/7/0 cause kled and illaoi (tentacle lady.) were camping his turret. after I swapped with teemo so he got mid and I (twist) got bot,bla bla bla...draven calls EVERYONE noobs casuals(in a casual gamemode ) and some things I don't know fit the LOL TOS.....tells zed he is trash(including me and teemo) tells him to kill himself. AND tells him he should have done better with our jungler camping him. youknow? the one he already called a noob. trash. report for AFK. ect. (but eventually the jungler left due to how much draven was beating him up :(... ) he used,the exact person he beat up and made leave,to keep his insult valid and explain how somebody was bad (and be aware zed just got in free rotation. have to start somewhere.....) blamed everyone for feeding. even when the game ended then he just spammed feeded(or was it feeder...) in chat. now for the part that I was focused on.... why? why be so mean to a person clearly outmatched? why beat up somebody for not pinging?(I was dead and kled has charge. there. I admit I should have pinged but he shouldn't had spent like 3 minutes chatting on how I was a bad casual,trash,uninstall,go play gamecube for not pinging. and I think that was going to ALL his teammates.)why be so mean on a game you can play for years,every day. this isn't football or something where you enjoy doing it but it takes time to schedule and travel,and at only a certain time of the year. the questions I have for you are... why are some people so toxic? do you get really mad for losing a casual match? have you even done something,or maybe have been a target of something like this? I don't feel too bad. draven isn't free RN so the person was clearly a better player,payed or just didn't get other champs. but the odds are in the things that would make him either think he is better then others or spend cash to win. have you ever bought a champ and why? I have seen some angry players. be it in a FPS,RTS,adventure,party or simply on any game with built in voice.....game. but I never found out why there angry. I spent a long time typing this and as I said,i did It before but tabbed and It got deleted xD and as I said on that one. I may look like I have a problem,i may look like a sore loser. but this feels like the perfect place to find out why toxic players are toxic...no offense to you.