I pretty much take it all in stride, but if I had to choose, I'd go with any death that seems to be the result of a jump button misfire. The most common occurrence is on the barrel board, at the top of the center ladder connecting the 3rd and 4th girders. I'll climb that ladder, racing an oncoming barrel (on the 4th girder) to the top, knowing that it's going to be close. I'll get there first, with enough separation to execute a back jump. I face right, press the jump button, and . . . nothing. The barrel rolls into me, and I'm well on my way to another game over.