It is a good question, and apparently several people keep asking it. I found a a visual representation of the problem:
You can find the original here, with many other interesting comics.
The interesting thing is that it seems that coding right and coding fast are like oil and water (or, to quote from the Godfather part three, like money and friendship). But is it true?
At the beginning, it surely is. But, after applying - and applying, and applying, and repeating and repeating all over again - you will actually be able to code right AND fast. That's where katas come in handy. Who knows, you might also be able to exit the "are you done yet" switch before requirements change...