The perpetiual toddler sliding machine

Last week, one evening before bed, we went to our local park to play with Davis and enjoy the summer weather.  While at the park, we discovered that we have a perpetiual motion machine.  Davis went round and round on the playground equipment going up the stairs, to the slide, sitting down and sliding down all by himself.    He did this at least 15 times before he was distracted by a 3 year old.