What PC specs are ideal in order to run a Linux distribution, flawlessly?

As a Windows user, all I know is that every PC will run Windows almost without any issues. All the drivers will be detected, no loud fan, etc, etc. Why is it that for some people, the various Linux flavors will "simply work out of the box," and for many others, they will have to spend time and effort, tweaking this n' that to get it work correctly?