> Worse than the Fujitsu Horizon system that lead to deaths due to stress and suicide, innocent people being put in jail etc...?
Horizon had really bad bugs, yes - but it wasn't the software that caused the cover-up or the miscarriages of justice: it was the management of (then-)privatized Post Office Ltd that decided they could not afford the risk of losing big government contracts if any word got-out that the system was making fundamental ledger errors. Most of everything else can be blamed on the sheer separation between the devs and the actual end-users: these problems could have been caught and fixed if the Horizon tech-support people weren't 100% subordinate to upper-management: if I learned that our support people were using phone-scripts that were as bad as the PO's I'd threaten to resign).
(though I'd argue the real fundamental problem here wasn't technical, nor managerial, but a simple consequence of the UK's entrenched class-system: subpostmasters generally don't read Classics at Oxbridge, which means in the eyes of the establishment that they're probably the ones at fault)
I'm not mad at the ICL/Fujitsu devs - they were severely understaffed (I gather it was literally just 4 people?), but I am disappointed (and in a state of disbelief) that they evidently didn't have any devs competent enough to know how to design a transactionally-safe retail POS system in the first place (and P.O.S. is the word...): hiring and retaining good people would have avoided this episode entirely (...though no-doubt something else would have led to a similar management scandal eventually - it's in the nature of almost all large UK businesses at this point.