Actually, I know a number of developers who have some sense of what a user interface should be like. But I also know some other developers, who when charged with creating a UI create monstrosities like the one below:
What's wrong with this dialog box? Click to see it at full size.
For more on this dialog box, see this entry in the blog Coding Horror.
If you're short on user interface designers, you might do well to follow the advice in this blog entry: Never design what you can steal.