Navigation skills

Travelling today from a barmy -7 degrees perfect snow conditions in Keswick to + 11 rain in the French Alps was quite an experience. The Sat Nav which is a woman for some reason decided to have an off day, why I ask myself did she decide to leave the easy motorway and head up a difficult Swiss mountain pass, with only a couple of hours left of driving after 15 hours on the road. SHE was not popular! Now this is the thing I can't get my head round. It is a piece of software, why trust this when you have a map in your lap! Why think that this is  a real woman. Who is now not trusted!