It's hard to generalize as domains vary greatly, but in general abstractions can account for more than enough extensibility unless the requirements are extremel

It's hard to generalize as domains vary greatly, but in general abstractions can account for more than enough extensibility unless the requirements are extremely vague and not well defined. This tends to be the case of why so many changes are constantly needed, because usually Product and Design are not defining requirements with abstractions in mind. Domain Driven Design basically aimed at tackling this issue, by trying to synchronize abstractions across departments, so I get that there are no easy solutions, especially in large orgs.