The way things should work: profits made in a country are taxed in that country.
The way things should not work: a company doing business abroad pays taxes both at home and abroad.
The way things break: subsidiary company makes "no profit" (no tax) because it pays hefty license fees (100% net income) to my headquarters company in Ireland. Ireland does not tax licensed technology abroad. I pay effectively no taxes (and instead pay clever tax accountants, who are cheaper).
This is an article is an attempt to remedy the situation where companies can chase low tax structure to literally any country which will offer a favorable deal. It is understood that you can't do it one at a time ("we'll just fix Ireland because they're the problem"), because there are many countries willing to offer such arrangement (Bermuda, Curacao, Panama, Iceland, etc.). This is an attempt to get to the 1st and 2nd point, while disallowing the 3rd.