With biscuits, it's putting my hands in the dough (I think I have issues with dough in general). It's a very unpleasant consistency, and it just sticks to everything no matter how much flour I use for dusting. Because I find that last bit so unpleasant, I haven't gained enough practice to make good biscuits. 

With pie crust, even though I use a recipe, I can (or could—I haven't tried pie crust in a while) never seem to make enough to cover the pie plate, so there are lots of weaks spots and holes in it. Doesn't make for a very pleasing pie.