The difference
The duller the blade, the more likely you'll have an accident. Of course, if it's really dull, then an accident, while common, may not be too serious. However, if it's good and sharp, then an accident is very uncommon (because the knife always goes where you expect it to), but bad when it does happen (losing fingertips, that sort of thing).
Generally, if a knife is too dull to cut me, I find it pretty useless for cutting something else.
