"If one does not expect it, one will not find out the unexpected; it is not to be tracked down and no path leads us to it."
It's a lovely paradox. It's particularly true of travel. Some people go to the most surprising places and never experience the surprise, because they are not open to it.
The 'fat white woman whom nobody loves' doesn't experience the vastness of the desert, but the sand getting in her hair.
I found a most surprising experience last week, in the Loire valley. I'd gone to look at chateaux - I ended up listening to cajun music at a village fete, the Stuffed Tomato Fair in Rilly-sur-Loire, eating salmon-stuffed tomatoes, and admiring the Honda motorcycle lovingly created out of choux pastry by a local patissier.
(Why stuffed tomatoes? Because they grow tomatoes in greenhouses nearby.)
Welcoming the unexpected is about noticing the little signs that tell us there's an adventure down this road. The poster for a local fair, the busker playing a tune you recognise from somewhere, the procession heading down a street (it might be a jazz funeral or a fourteenth July procession, like the one I saw in Blois featuring fifteen fire engines)...
But if you don't expect to find the unexpected, all you'll find is what the guidebook tells you.