A common scenario: A UX is designed, it gets built and deployed.
Over time, people (for example execs, or devs) add new features, images, buttons etc without going through the design process. With each addition, the UX becomes slightly more diluted until eventually it no longer solves the problems it was intended to.
Is there a word to describe this?
I think the term you are looking for is Feature creep.To quote a definition found on SearchCIO
Feature creep (sometimes known as requirements creep or scope creep) is a tendency for product or project requirements to increase during development beyond those originally foreseen, leading to features that weren't originally planned and resulting risk to product quality or schedule. Feature creep may be driven by a client's growing "wish list" or by developers themselves as they see opportunity for improving the product
Though this is more of a Project management term ,its applicable to your question since the decision to make these changes or upgrades are ad-hoc and not planned with an objective to implement it with an UXD approach
Code has Code Rot.
UX has UX Decay.
I like to refer to the specific things glued onto the original as barnacles. They make your ship slow and ugly, and then it sinks.
I could not come up with a word that defines your state(maybe: abolished/annihalted!). But the cause of this state can be defined relatively!
Ethnocentrism is making value judgements about another culture from perspectives of one's own cultural system. It is the belief that one's own cultural group is somehow innately superior to others.
From software development process perspective, we can replace the word culture with XXX team.
What surprises me from your query is that if images/buttons/features were added,it means web designers were kept in loop of the changes, but why not the UX people?
On a lighter side, we can enhance the following link by adding the third slide saying "How the UX was forgotten!" for your current scenario! :-)
I always use the term Feature Accretion.
I use as a metaphor a coral reef. When you first ship, it is a gleaming beauty. Over time, it settles to the bottom of the sea, and little features accrete to it. After a while, the shape is not even recognizable, and it's some globulous organic form. And if you dig deeper into it, you may find that the ship has decayed away entirely.
