Now there's a related problem in the premise: it pre-supposes that the company has an unlimited amount of valuable work to be done. If that were the case, all companies would simply expand their workforce as much as possible all the time, only constrained by money running out (which itself would be an exponential increase since "valuable" work presumably leads to more money in future). In reality, companies do not prioritise expansion above all else. In fact any time a company pays a dividend to its shareholders, or otherwise refrains from spending cash reserves on new hires, it's recognising that it cannot invest profits in an effective way into its labour force.

When framed correctly (there's effectively an unlimited labour supply for most companies, and effectively a limited demand for staff) then the question becomes "shall we hire an engineer to fix security bugs when we don't need an engineer for anything else?".