I'm going to rant about why I don't like bad cosplaying because this topic has been eating away at the back of my mind. First of all I don't cosplay because I'm not interested in that but I do like seeing good cosplaying. I will make a list and pictures of bad examples.
If you are fat, chunky, overweight or big bone, don't cosplay as a sexy character. No one wants to see your jellyrolls hanging out. If you are overweight, look for a character that you can cosplay as and that you can keep your dignity.
Don't put on a cardboard box and say you are cosplaying as a mecha. It makes you look like you have "special needs"
If you are a man and you cosplay as a woman that makes you a crossdresser. If your excuse is "I lost a bet" no you did not. you choose to dress like that because deep inside of you, you like to wear women's clothes.
If you cant make a decent costume, then buy the right one. In the picture below, you can see that they must have bought their costumes at a cheap store or they are just cheap bastards and went with the least expensive thing on the rack.
I know that I'm going get some comments saying:
"lol, americans should not cosplay"
"cosplaying is fun, you sux"
Well, I have seen awesome american cosplayers and I know that its a hobby. However if you cosplay, you should do it right at least.
Now i give you a vid of more bad cosplayers.