On October 11, 1963, my suggestion was to pass on a request of our customers to relax the ALGOL 60 rule of compulsory declaration of variable names and adopt some reasonable default convention such as that of FORTRAN. I was astonished by the polite but firm rejection of this seemingly innocent suggestion: It was pointed out that the redundancy of ALGOL 60 was the best protection against programming and coding errors which could be extremely expensive to detect in a running program and even more expensive not to. The story of the Mariner space rocket to Venus, lost because of the lack of compulsory declarations in FORTRAN, was not to be published until later ... (car hoare acm turing award lecture, october 27, 1980)

in his paper the emperor's old clothes hoare talks about failures in software development in the first 20 years, his work at the elliott 503 mark II software system and why it had to be abandoned

...Over lunch our customers were kind to try to comfort me. They had realized long ago that software to the original specification could never have been delivered, and even if it had been, they would not have known how to use its sophisticated features, and anyway many such large projects get cancelled before delivery. In retrospect, I believe our customers were fortunate that hardware limitations had protected them from the arbitrary excesses of our software designs. In the present day, users of microprocessors benefit from a similar protection--but not for much longer. At that time I was reading the early documents describing the concepts and features of the newly announced OS 360, and of a new time-sharing project called Multics. These were far more comprehensive, elaborate, and sophisticated than anything I had imagined, even in the first version of the 503 Mark II software ...