[emsal]

Doesn't this fundamentally misunderstand the Pareto principle? The 80% and 20% of causes in standard examples don't refer to portions of a sequential effort, but rather slices of competing agents/producers/customers in an economic system. Like, 20% of clients account for 80% of sales, that kind of thing.

[minitoar]

Seems analogous to me. “20% of the functionality (in a product) is 80% of the work (to implement it)”