How much time do I have to work on a study?
Researchers can specify the "Estimated Completion Time" for a study or in other words, how long a participant should approximately take to complete a study. Researchers also specify a "Maximum Completion Time". You should always aim to complete the study in less time than allotted by the researcher.
This mechanism ensures that studies are completed in a reasonable time period. If you take too long to submit the study you are participating in, then you'll time out and the researcher may reject your payment.