wow, i'm really contributing now!
i think the disposables are made cheap and dull. they used to be sharp, 'razor sharp' 10, 15 years ago. i could get a whole shave out of one with my strong beard. now adays, it takes 2 to do it, and they're dull right out of the package. reason? two reasons in my opinion:
1: all the doosh bag lawyers made everyone afraid of lawsuits, so the razor companies make them dull so you won't cut yourself and sue them. (who would think that a knife edge would be sharp!? duh.)
2: they make them dull because the company want you to buy the razors they sell that have replaceable blades, because those items sell for more and they make more money on them.
but at least the disposable ones are dull enough that they aren't as dangerous for shaving your dick and balls.