You've got your work cut out for you!

Today my mother informed me that "You've got your work cut out for you" does NOT mean that you've got an easy job ahead of you. Until today, when I heard it used the way she explained in a TV show, I've never in my life (ok, I'm only 21 but still) heard the phrase used to mean that you actually have a difficult task ahead of you. And yet a quick google seems to show me that this is exactly what it means.

Can anyone offer any suggestions as to why everyone I know may have been using it to mean that one actually has an easy task ahead of them? Or have I just been completely misinterpreting things for the past 20 years? :(