Multiple regions support placing workloads closer to your customers, for example, by operating one region on the US east coast and one region on the US west coast, or operating a region in Europe and another region in the US.
Regions are helpful in several ways.
Regions can support disaster recovery solutions: One region can be the primary site and another region can be the recovery site.
You can use multiple regions to address data privacy laws and restrictions in certain countries by keeping tenant data within a region in the same country.
The distance between regions can be rather large. This design uses two example regions, one region is San Francisco (SFO), the other region is Los Angeles (LAX).