The breathing-assistance machines tended to be bulky, expensive and limited in number. The plan was to build a large fleet of inexpensive portable devices to deploy in a flu pandemic or another crisis.

Money was budgeted. A federal contract was signed. Work got underway.

And then things suddenly veered off course. A multibillion-dollar maker of medical devices bought the small California company that had been hired to design the new machines. The project ultimately produced zero ventilators.

That failure delayed the development of an affordable ventilator by at least half a decade, depriving hospitals, states and the federal government of the ability to stock up. The federal government started over with another company in 2014, whose ventilator was approved only last year and whose products have not yet been delivered.