Here's why you shouldn't report everyone everytime you lose
How many players, yourself or teammates, all chat report x and y and z every time they lose? It's a ton of people who do this and you can't lose a game without someone on your team saying this. Well reading the Tribunal FAQ I ran across this gem.
How many reports put you in the Tribunal?
Typically a large number of reports are required before a player appears in the Tribunal, so if you had a bad game and are reported, don’t worry! You will most likely not end up in the Tribunal. The Tribunal does take into account the credibility of the people who file reports. If you are a positive player in League of Legends and only report when the offenses deserve it, your reports will actually be worth a lot more in the Tribunal than someone who abuses the reporting system and falsely reports lots of players. Generally, players who follow the Summoner’s Code and respect their fellow gamers should never be concerned about seeing the Tribunal.
So just for everyone to understand, if you constantly report people Riot will pretty much decide your opinion matters very little to not at all and the constant stream of people you report will not be sent to the Tribunal. So if you run across a player who actually is abusing you or breaking other rules that report won't ever see the time of day because you already ruined your credibility. Just something to think about next time you want to report a player for having a bad game.