[singular]

This, to me, has a lot to do with the languages and tools used on a project - the more 'locked in' to a structure you are, the bigger that cost will be when something changes.

This has been a concern of mine w.r.t. oop as implemented in C# (and by extension java), as the structure can be very costly to change down the line when the inevitable 'pivot' in implementation occurs.

[jakejake]

True and it seems like no matter how much foresight I have and how much abstraction we code in, eventually some change comes along that nobody saw coming.