I can imagine that for some people it could be a false safety net. Its simplicity makes it look like some "magic arrow" that will lead you to safety no matter what. But when it breaks the people unflinchingly believing in this device are in big trouble.
It can be backup for people that know what they are doing but like I said I can imagine some people not paying attention as to where are they heading because they have this device with them and "it will surely take care of their return".
Well, it can be said for normal GPS too, but this is just too simple that it challenges to just turn it on and "relax".