Hate to agree with RPM but self launch is a core skill.
The funniest thing i have seen is a tethered launch go wrong with the kite tomohawking from left to right as a gust came through and then the kite self destructing.
With a tow ball or post if it goes t!ts up, it happens so quickley and you have no chance of getting back to the bar and flagging the kite.
4 weeks ago we saw a 2 month old, 2011 rebel which had been ripped to shreds because of this method of relaunch. It alternated between the beach debris and the hard thorny bush at Shoalwater in Safety Bay, when asked if we could repair i suggested that the guy check his insurance!