Why is it not safe to save everything on the desktop?

Write a method so that the main() code below can be replaced by the simpler code that calls method original main(): public class calcmiles { public static void main(string [] args) { double milesperhour; double minutestraveled; double hourstraveled; double milestraveled; milesprhour = scnr.nextdouble(); minutestraveled = scnr.nextdouble(); hourstraveled = minutestraveled / 60.0; milestraveled = hourstraveled * milesperhour; system.out.println("miles: " + milestraveled); } }