What does "as the product sells" mean?

What does "as the product sells" mean?

The eBook Competition is for electronic books which have been professionally published and are for sale to the public  Your entry should be a PDF of the work which any customer could purchase. We have received a staggering number of Advance Reading Copies (ARC), and even a few obvious Word-generated PDF versions of manuscripts. When the filename includes such things as "ARC," "edited version," or "print proof," it gets closer scrutiny. If an uploaded file is found to be an ARC, edited manuscript file, or a proof or galley, it will be disqualified. Entries should be clean, well formatted, and free of errors. Judges will consider these items as part of the evaluation process.