Shout out to the Jeff Geerling video about this

Author needs to decide which end of the stratum stack they want as the top.

This design from 2010 had at the top stratum 1 sources at Australia's National Measurement Institute (NMI)

Among otherwise comparable candidates, the lower stratum carries more weight.

Each decision solved the problem in front of it. Nobody was asked to look at the sum of all actions.

This is the perfect description of Telstra as a company.