This is somewhat true, but you structure the code in a way so that rewriting any one part is easy. You keep your modules fairly large, your abstractions thin, and the code very literal. It's much easier to do a total rewrite on code that's like this than when you abstract it out a great deal.

It's very quick to write code like this, and the maintenance cost of this isn't as large as you might think (honestly, after you get used to it, you often end up preferring it. It's very, uh, blunt, for lack of a better term).

Edit: Worth noting that these rewrites aren't always due to a change in creative direction. There are often ones for technical reasons.