Letting a System Give Ridiculous Answers

Here is another example of a computer giving a ridiculous answer. When I book a hotel, Booking.com will automatically suggest an airport transfer. OK, but not when the airport is 200 kilometers and a long ferry ride away. Providing meaningless answers to your users is not a trivial problem that you can brush off. It undermines the confidence your users have in a system, usage drops, and shadow systems in excel proliferate. Do you have a policy to build sanity checks into your systems?