Even NASA can fail. In fact what self-confessedly drove Elon Musk to Martian missions was precisely the feeling that they'd failed in that ambition too. It begs the question though as to what failure is anyway, for to my mind the overriding failure in life is not to venture much for fear of it.
The X-57 ('X' being for Experimental) took the same path as other electrical projects in basing itself upon an existing airframe in the form of the lightest twin-engine airplane available viz. P2006T. Italian aircraft have always been among the most imaginative, invariably as stylish as the efforts of its fashion houses.
Budgeted at $100 million, an 'unforeseen' safety issue involving its propulsion system would apparently take that to nearer $165 million... and I thought I had problems. It is not by a long way the first fixed-wing type to use a distributed array of motors, NASA themselves long having used the approach on delicate solar-powered types which, of necessity, had to split the load along the length of each wing.
Initiated as long ago as 2016, too, it may arguably have been the inspiration for a small number of projects in Europe and the US with commercial orders... not least Electra.