Design should convey its message, even if you miss important details. But if you aren't specific, design might be done for design's sake and your message may get lost. For instance, this box, instead of saying "No matter where - Nature Valley is there." instead says "the path - Nature Valley is there." (umm... what path?)
However, that's minor. This is more troubling:
Each package contains two bars. Eat one and it's 90 calories. But eat them both and it's 190 calories. Where did the extra 10 calories come from? The wrapper?