I guess that rather than being afraid that I would
hurt someone, I've been afraid quite a bit when after a throw, uke is slow to get up that I have
hurt someone (I haven't as of yet, though . . . yet
In Colleen's analogy with the car, I'm not afraid of crashing when I drive, but if I have a near miss, I am a lot more conscious of my ability to harm, and much more cautious and nervous for a while afterward. Similarly, if you throw someone, and s/he is possibly hurt, you have a slight fear of hurting anyone else afterward, and you may become more cautious (at least I do).
I answered "yes," even though I don't have a constant fear of hurting my uke. I like to throw hard (only when I know my uke can take it, of course
) but even so, there is always a little twinge of worry in the back of my mind, but I accept that I may hurt someone, as I accept that I may get injured myself (though I try to avoid both). It's a part of the art, and it wouldn't be nearly as enjoyable without the pain.