It happens. People get reported for intentional feeding when they are actually unskilled. People get the idea that players can get suspended for being reported as an Unskilled player. Players tell others to report (for unskilled play) and the targets think it's the attempt to create falsified reports to get them suspended unjustly.
If Riot Games really wants to make matchmaking more accurate with Unskilled Player reporting then the following should be done.
1. Remove Unskilled Player from the report player menu.
2. Add a new rating icon near the summoner's names in post window.
3. Have a window pop up with thumbs up or thumbs down when the rating icon is clicked.
Thumbs up will be for good play, thumbs down for bad play. Now when a player wants to rate another as unskilled and let them know it, they will say thumbs down instead of reported and there should be far less confusion on the matter.
A relatively doable change to the interface imo.