The way I've brought the concept of "time" into this project is by examining the time taken to perfect different tricks, from the first time they are tried to when they're landed and all the falls and injuries suffered in between!  This video of one of my favourite pro skaters, Chris Cole is a perfect example of what every skater must be willing to go through at some point or another.  This trick took him a total of 68 tries and most of the day, suffering greatly in the process.  Enjoy!