|Sweet tats bro! So br00tal|
Obviously, since metalcore is the personification of everything wrong with metal, it has its fair share of annoying vocals. Metalcore especially feels the need to insert whiny vocals in every damn song, no matter how good their vocalist is (and some are actually good, I'll admit it). Clean vocals in these songs sound like kids going through puberty. This is possibly because most metalcore bands haven't reached puberty yet.
If you're going to do something, do it right.