Do you have a paper map in your car? No, why would I need that?
If you are a Verizon customer in the U.S., you were just reminded. A large chunk of their network was down for half a day, leaving frustrated customers depending on their atrophied geographical memory. Verizon says the culprit was the usual botched network upgrade, not evil hackers. Some Europeans are better prepared, having routinely been subjected to Russian jamming of GPS and Galileo navigation.
When was the last time you revisited the risk evaluation of your critical systems? The threats are changing and increasing, and your risk evaluation from one year ago no longer applies.