Why do presidents...?

use auto-pens? presidents do not have to really do anything besides the interviews, vacations, and signing bills. What is so tricky about the last one? I want a president that has to read the bill and for them to put their own genuine signature on there, not some machines. the only reasons that i see them using auto-pens would be because they are even lazier than we assumed or so they can deny signing a certain bill if it did not go according to plan. after all, you have to remember whom we are dealing with here