Just wait until you get the edge of your finger in between the case and the bullet when you are seating bullets. If the case is champhered, it makes a nice even cut.
I have used this "Mistake" many times in trying to explain just how little resistance is needed to make a perfect taper crimp. There's a lot of leverage there! I've never caught my finger on the edge of a case, but I've sqoze it a time or two.