When I used to post HITs, I would get so many people doing my HITs that clearly didn't even look at the instructions. I would post qual HITs for the forum saying "This HIT is only for MTurk Crowd members. If you don't enter your forum name I can't verify you and I will reject you." People would just sub stuff like "not a forum member" or they wouldn't enter anything at all and just sub it blank. So I would reject them. They would almost always start sending me messages trying to argue with me about why I'm a horrible requester for rejecting them and that I should overturn their rejection because they "did the work." I even had one that repeatedly threatened to report me to Amazon. It was very eye-opening. I can't imagine what these requesters that are posting HITs on here day in and day out have to deal with on a daily basis.