When creating an Azure storage resource, is the default/selected region random or it's a calculated recommendation?

When creating an Azure storage resource, there is a default, selected region in the location drop down.

Is this "randomly" selected or its a "calculated recommendation"

I'm asking because I keep getting the same selected region even with a second resource.

Also, my geographic location is nowhere near that selected region. The region I would expect is South Africa North or South Africa West