A lot of it is getting your bladder used to operating on a schedule, and that has to be done in steps. If your bladder is doing whatever, whenever, that's less controlled than if you've gotten it used to once an hour, and it's only when you've gotten it used to some sort of schedule that you can start slowly extending the intervals.
I can see where it's counterintuitive, but it's about taking a first step that your bladder can handle, and then going forward one step at a time by lengthening the time between voids.