When a print is done, you have to click the "Print removed" button to re-ready the printer. In the popup that shows when you click this button allows you to mark your print as "Not good", even though it might be 100% done.

We've all tried getting back to a print that is supposedly "finished", but is just a blob of plastic or a bunch of spaghetti... In this case, SimplyPrint allows you to mark the print as "Not good", which puts it in a box with all the prints you have cancelled.

This means, that in statistics, the print will not be logged as a "successful" print, just because it reached 100% completion.

But most importantly of all, if the print was printed through the print queue, marking the print as failed restores the "Amount left" count on the queue job.