I just tried a 50-cent "Musical Complexity Survey" HIT. It was very quick and easy to complete; the survey itself involved only 2 short musical samples, and a simple question, all easily finished within about a minute. But at the end of the survey, there was supposed to be a confirmation code, and I did not see any such code. So I am not going to get my 50 cents. I returned the HIT.
No no no.... If that happens, you write in the box that no code was given at the end of the HIT and hope for the best =) Well, that's what I've done. Haven't received a rejection yet *crosses fingers* but the one requesting was a University of some sort. I guess it depends on your number of approved HITs though...and how willing you are to risk a stray rejection. Crap. Maybe a block, too. IDK. Nevermind. I talked myself out of doing it that way in the future.
I've done that several times with positive results. I figure I've already taken the survey, so I'm not going to let them easily get the work for free. I accidentally let enough surveys time out while I'm trying to wait for the timer to get high enough - so that's my charity work on here. If you wanted to be nice for the next person you should've emailed the requester and let them know about the issue.
Whenever this happens, I go to my "HITs assigned to you" tab and expand the details of the HIT, then use the "Contact the Requester of This HIT" Link to send them a message. If the HIT is going to expire soon, I'll go ahead and submit with "No Code" in the box. If there's a long timer, I'll try to wait until I hear from the requester. If I don't hear back, I return it.
Yeh, I wanted to be nice for teh Next Person. But I'm still learning MTurk (started last month) ... and I discovered that I don't know how to find a requester's contact link, after I've returned their only HIT, and there are no more current HITs from that requester, and I've already forgotten the requester's name.
Update: The requester has posted new HITs, now with a more proportionate reward of $0.20. However, the new hits require Categorization Master qualification. https://www.mturk.com/mturk/searchbar?selectedSearchType=hitgroups&requesterId=A3C5JTKBHDWZ40