In order to ensure the highest quality results for Mechanical Turk Requesters, we monitor and sometimes regulate the volume of HITs that each Worker completes. This could occur at anytime while working on Mechanical Turk.
During a performance quality review, a temporary hold will be placed on the Workers' account. In most cases, this hold lasts for less than 24 hours.
The triggers for such a performance review are proprietary, we do not specifically publish or share them.
I hope this helps. Thanks for your participation in Mechanical Turk.
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