The fact that you don't know might indicate that you need a good
swift one! I believe a kick in the pants is the equivalent of a
"wake up call", usually a means of correction, discipline and
motivation. Example: Jim forgot to pick the kids up from school
again today. He sure needs a swift kick in the pants!" I picture
the kick being delivered to the rear of the pants rather than the
front. So, in essence, you need your a** kicked!