If you've done anything like crowd-source work before (the closest I can compare to is Amazon Mechanical Turk) then it is VERY plain to see, that the tasks offered as work through Appen, are a complete waste of time.
I have not seen a micro-task offered above the $0.20 mark. In 6 hours of doing these low-pay micro-tasks with Appen, I make $0.90. I made almost double that with Amazon Mechanical Turk the first two hours as a brand new user with no qualifications. So the entire application process for Appen, and qualification tests for Appen are a complete waste of time.
I should also say that I took the qualifying tests on AppenScribe for transcription work, which I passed in the 90th percentile, and have sat around for a week with zero work offered. It's sad, I was hoping to made some dollars at least. But no.