I see two obvious mistakes
on many boats.
are so close to the rail that it is possible to fall off the boat
The tethers are to long and do not prevent you from falling overboard
Most tethers are designed as to restrict your movements so you can not get in a position where you could fall overboard
. Like a dog leash. They are only designed to stop your mouvement.
In other post many stories of sailors drowning while being dragged along side the boat
This would not happen if the set-up was such that it is impossible to fall off.
Also if you fall off, the clips are probably unable to resist the massive energy from stopping your fall. Specially if they end up with a side load.