What kind of software was this? I've been in a similar project where we would get beautiful requirements from the client and implement them flawlessly on time,

What kind of software was this? I've been in a similar project where we would get beautiful requirements from the client and implement them flawlessly on time, every time. I've also been puzzled by this a lot and wonder why other projects can't be the same. The thing missing from the story is the complexity of the software and how long the client spent upfront on designing those requirements before handing them off. This was very trivial applications with few states, no UI and clear input and outputs, nowhere near a big modern web service. If our implementation was according to spec but not what the end customer really needed it would still not be counted as a bug, it was the clients responsibility for writing a bad spec, the client was very much aware of this so we also hardly ever got any bug reports in that sense. It was waterfall it a nutshell, assuming the first design is correct and resource optimizing every step of the way for it. You couldn't replicate that process onto an app with a big UI footprint and quickly changing requirements which requires more iteration rather than upfront design.