Why does the routing work this way?

Focus Driver
Focus Driver Registered Users Posts: 39
Master Explorer
I make a regular run from Newport (South Wales) to Poole (Dorset). My TomTom 520 always wants me to use the M4/A34/M3?M27, but that's nearly 50 miles further than my "optimum" route down the A350 so I have to ask for alternatives (which it finds).

There is a useful short-cut across the toll bridge at Bathampton, and yet I am never offered it until I am within a few miles of it. At the moment, one of the main bridges in Bath is closed, so coming back the TomTom wants to route me through Bradford-on-Avon to avoid Bath. It still tries to drag me back to Bradford even when I'm nearing Bath, until it eventually realises there's a cut through and finally "comes my way". The toll doesn't operate at night anyway.

Further south, it offers a route winding behind Melbury Abbas (along some very narrow lanes) when actually there's a far shorter and easier route through the village (which it offers at the last minute).

I know where I'm going, and I use the TomTom for warnings of traffic delays and as a "moving map", but these consistent errors are annoying. For somebody actually needing the nav input, they would be given non-optimal routes. These are specific examples, but I can't believe they only happen to me.