Have you ever parked your trailer or ute on uneven ground and then had trouble loading your bike? The ramp tends to slip downhill under the weight of the bike, sending you and your pride’n’joy for a less than gracious street-side exit.
It will depend on the type of ramp and what vehicle it is attached to, but you should have some sort of method of securing the ramp when loading the bike. A hook or lip will stop the ramp slipping backward and falling off the trailer. Something as simple as a bolt can stop the ramp slipping backward, as well as sideways, making loading a bike much safer.