A disadvantage is that the kite may keep pulling hard and cause injury to the sailor. A wrist leash must have a velcro cuff so that the pilot can take off the wrist leash in dangerous situations. The wrist cuff must be very strong because it needs to hold the kite at full power. Please note that almost every modern kitesurfer uses a wrist leash in combination with a quick release or trip line, which reduces the risk of injury to the sailor. Also while the kite is spiraling down it still creates a pulling force and is not fully depowered.
Bars are examples of the trip line system.
A short leash from the sailor's wrist to the shackle, pulls the shackle open when the bar is dropped. The shackle instantly opens and disengages one line from the control bar. The wrist leash has to allow full arm movement otherwise the risk of unintentional or premature quick release is increased. Both systems mentioned above cease to be automatic when the sailor is hooked into the harness line. When hooked in, the sailor has to manually operate the quick release.