Students are always looking at how they can improve their kicking, jumping technique, patterns and sparring abilities. This is a multifunctional approach to achieve this:
Perfect kicking practice and drills
Lower body power improvement
Balance and coordination improvement (proprioception)
The last element is quite often neglected and is massively important for your stability whilst performing techniques as well as reducing the risk of trauma injury and overuse injuries. Take a look at the below video clip which is produced for football however it is very relevant to TKD, many of the exercises can be done without stability disks but are improved with them.