Because it's much easier to change software than for example a bridge. I don't see it as a bad thing as long as all sides are aware that changing requirements changes the deadline as well.
In my experience, this could not be further from the truth. There is simply no awareness that change remains expensive it's just that now the process allows it without any fanfare whereas before a change was a big deal.
Not saying that change requests are the way to go but certainly an understanding that change is not free would go a long way
Maybe there’s not as big a difference as people think, though?
It occurs to me that is actually possible to change the design of a bridge late in the day. The extra dampers to fix resonance problems on London’s Millennium Bridge are a nice example.
(I don’t actually know which it is; maybe it’s both)
It's extremely dangerous, and software is quite comparable to a bridge. Imagine starting at both sides of the river and the bridge not meeting in the middle.
Changin requirements / features is very simular. And while on paper it sound like no problem, thats when you need to push back against your PO/Whoever is pushing the change.
I'm not sure what the point is, but it somehow fits into yours...
We can pretend we're building a bridge, but there could be another company, that is more comfortable with changing requirements and may deliver their product later, but more suited to a market.
Ultimately all software becomes very inflexible if you cannot get the source code or especially flash firmware.
Software looks as if it should be more flexible than concrete.
But it really isn't.