There will always be miss-steps. But I don't think you ever achieve great design without being very opinionated. I feel that it helps to edit yourself.
I really hate all these fake textures they are going though.
Windows XP didn't ship with a user-level calendar. If Apple had a calendar before 2006, they'd be winning the calendar design front without much effort.
That doesn't mean the result of said thought was good, however:
http://i.minus.com/dQhzPuq2CZUc/264182-apple-mac-os-x-lion-1...