Can anyone explain the algorithm used by the MIB3 SatNav in a 2021 Superb?
When I ask it for a route it often gives me something very illogical, sometimes using B roads instead of A roads, and clearly at odds with the fastest route suggested by Google Maps. I don't mean the way a satnav can sometimes suggest a minor road that cuts a corner to save 30 seconds, but a weird route that can be much slower. If I ignore it, and follow what I know to be the best route, it nags for a while trying to persuade me to change, but eventually gives up and recalculates for the route I'm on, and that invariably makes the arrival time much earlier (can be 15 minutes earlier on a 1 hour journey)!
I've used other systems where it's possible to select between fastest/shortest/most economical, but I can't find any similar option for this. If I ask it for a selection of routes it will give me three, but even the fastest one is almost always slower than the one I know to be best. It's not due to traffic congestion (I've checked).

These days I've taken to ignoring it and using Google, especially if I have someone in the car that can hold a phone & give me directions, which rather negates the point of having a built-in system.
Any ideas?

I suspect that the built in uses the TMC if yours is working from traffic announcements, whereas Google maps is essentially spying on you and uploads the data and shares to other users of google maps for traffic, so it’ll be much more accurate

My MIB1 in the Octavia gives me the choice each time, fastest, shortest, eco.

You made me think & I don't remember having this option in the Superb MIB3.

 

I have the online "traffication" & Skoda connect services activated so I'd expect it should have real-time updates through the internet for traffic & delays etc.

 

I don't often drive many complicated routes but I'll try driving with the nav active more often.

It nags you to do this anyway with the suggested routes screen each time you start the car.

Thanks for the suggestions, but I'm not convinced that it's related to traffic information, neither Google nor Skoda connect showed any delays on the routes in question. I can't remember if there's there an option to tell it to ignore traffic.