Reasons I do not want a satnav

I've just had a call from a bloke who is coming to our house to fix something.  He said he was going to follow his satnav to the village, which he confidently pronounces is 10 minutes away from his current location.

10 minutes later: panicky call: " Help!  Where am I!  I'm in a wood!'   Discussion concludes that his satnav has directed him to the wrong side of the river and  he is, therefore,  in the wrong county.   What's more, on enquiry it turned out that he did actually know where the village was, roughly - only because the satnav told him, he went another way.  Why do people believe what computers tell them, so confidingly?

If he has not been eaten by beavers, I expect another call when he gets to the pub, because satnav is no use in a village that only has one postcode anyway.

Give me a map any time.