Steven Denbeste explains the difference between user friendly and user hostile - in short, it's usually a mistake to assume you know what the user needs:

Your job as a tool designer is to give your customer what he wants, not to give him what you think he needs. Your job is to let him do what he wants, not to force him to do what you think he should do. If a customer comes up with a hacky solution which works, let him use it. In that case, it means he's still concentrating on his problem. Once your tool gets in the way and tries to force him into some stylistic channel or other, then he not only has to concentrate on his problem but also on trying to figure out what way your tool is willing to allow him to solve it. Whether or not the result is "better", you've made the problem harder to solve, and that means it's going to take longer and require more effort. That's the opposite of what tools are supposed to do: they're supposed to enable fast solutions, not prevent them.

Something to consider next time you get ready to deliver....