Some developers don't appreciate the value of separating data from UI. A UI designer says, "Give me the data and I'll present it." But if they get a mixture of

Some developers don't appreciate the value of separating data from UI. A UI designer says, "Give me the data and I'll present it." But if they get a mixture of data and UI code, there's a serious problem, requiring a rewrite. If you're lucky, the project is already using UI templates, but that's no guarantee that they're flexible. It can be hard to keep a designer's interest if they're waiting on a complete refactor just to make a new UI even possible. The worst I've seen is where users have been encouraged to embed UI elements (such as HTML or nonprinting ASCII) in raw data or settings to trigger certain functionality. That'll drive a UI designer to drink.