Our main focuses for our product are around high quality, ease-of-use, and reliability. In our experience, MTurk exhibits none of those.
It requires a lot of work to get truly high quality results, and virtually impossible above a certain quality threshold. MTurk promises no SLAs and forces the customer to do a lot of work such as price discovery, building UIs, and quality control, not to mention how difficult to use their API is. Our philosophy is handle all of that complexity for the developer.
We've been inspired by our own experiences using easy-to-use APIs like Stripe, Twilio, SendGrid, etc., and wanted to build a similar experience for human intelligence. Hope that helps!