It works when they know ASAP after the abduction. Then again, there are always exceptions. Samantha Runnion was not recovered safe, unfortunately. God, these sick diddlys (meaning the amazinhunks who take the kids) deserve to die if anyone does.
Hopefully this media coverage of stuff will cause people to be a little more cautious and aware of what their children are doing. It is a shame that they even have to.