Babbage, as (necessarily) the first person to work with machines that can attack problems at arbitrary levels of abstraction, fell into a trap familiar to toolsmiths since, as described here by the English ethicist, Lord Moulton:
«One of the sad memories of my life is a visit to the celebrated mathematician and inventor, Mr Babbage. He was far advanced in age, but his mind was still as vigorous as ever. He took me through his work-rooms. In the first room I saw parts of the original Calculating Machine, which had been shown in an incomplete state many years before and had even been put to some use. I asked him about its present form. "I have not finished it because in working at it I came on the idea of my Analytical Machine, which would do all that it was capable of doing and much more. Indeed, the idea was so much simpler that it would have taken more work to complete the Calculating Machine than to design and construct the other in its entirety, so I turned my attention to the Analytical Machine."
After a few minutes' talk, we went into the next work-room, where he showed and explained to me the working of the elements of the Analytical Machine. I asked if I could see it. "I have never completed it," he said, "because I hit upon an idea of doing the same thing by a different and far more effective method, and this rendered it useless to proceed on the old lines." Then we went into the third room. There lay scattered bits of mechanism, but I saw no trace of any working machine. Very cautiously I approached the subject, and received the dreaded answer, "It is not constructed yet, but I am working on it, and it will take less time to construct it altogether than it would have token to complete the Analytical Machine from the stage in which I left it." I took leave of the old man with a heavy heart.
When he died a few years later, not only had he constructed no machine, but the verdict of a jury of kind and sympathetic scientific men who were deputed to pronounce upon what he had left behind him, either in papers or in mechanism, was that everything was too incomplete of be capable of being put to any useful purpose.»
--Lord Moulton, "The invention of algorithms, its genesis, and growth", in G. C. Knott, ed., Napier tercentenary memorial volume (London, 1915), p. 1-24; quoted in Charles Babbage Passage from the Life of a Philosopher, Martin Campbell-Kelly, ed. (Rutgers U. Press and IEEE Press, 1994), p. 34.