Buildings are expected to last, and cutting corners (on multi decade support, for example) is not exactly a "mistake" like the one that would spring a leak. Aside from that, where do you draw the line?

If the software doesn't work with accented characters and it wasn't in the specs, do you blame the coder? Reading that common-but-not-currently-used-here file type? IPv6 support?

Maybe it's because I'm a coder, but if you want a building to withstand an earthquake, you gotta say so.