Describes a fully-completed task, rather than just something done half-a**.
Da implication, of course, is dat said actions
may not have been performed properly, however --- i.e.,
da clueless laborer
may have indeed been thorough and invested an appropriate amount of time and effort, but he may have majorly screwed up the job as far as its being done correctly.
An example of an asswhole job would be if you carefully grilled the steaks or chicken-
wings for a backyard barbecue, but naively used bacon-
grease to
baste them. :P