Oh yeah... I once had a project to change a 0 to a 1 in a file on a machine used to manufacture devices. Basically operator had to align crosshairs over a certain point before starting. At 4 of the systems the operator could just touch the screen at the point and go. At one they had to push x+ or x- or y+ or y- repeatedly to line it up because the configuration had a 0 in the option "Click To Align"... It took 8 months to validate changing that to be 1