I see you guys sometimes send a complaint in about not being rewarded after completing a long survey. This just happened to me and I sent a note in about it. Here was the response:
Thank you for giving us a heads-up here in member support regarding the issue.
I am very sorry for how much inconvenience this has caused you but our records indicate that you were stopped from completing this survey because you did not meet the desired demographic criteria or consumer habits that our client was looking for. Our studies contain qualifying questions that need to classify respondents.
I understand your frustration yet I will reward you for the time you spent completing this survey by crediting your account accordingly within the next 24 hours.
Please note that our surveys do have qualifying questions at the beginning, middle, and at end of the study that can terminate or disqualify your participation.
Hope you will continue to participate in other survey opportunities with us.
My takeaway is that they should ask ALL demographic questions at the start because if I spent 20 minutes on a survey, I should not get kicked out at the end due to my age or race or whatever.