I'm the type of person who likes to plan. But I doubt that the average person anticipates all these career changes in advance. How could you predict the future that way? There are too many uncertainties.
We're still, as a society, built on the idea that a person will grow up, learn something in school, and then that will be his or her profession. "What do you want to be when you grow up?" we ask children, as if there could only be one answer, instead of several in sequence, or maybe even a few at the same time. student declares a major, and most people who are somewhat more sane than I was only pick one.
I don't think the world equips us very well to learn to be adaptable. I would imagine that since 11 is only an average number, people figure out how to make changes in their lives somehow.
Has your career turned out anywhere close to how you imagined it? Do you think the reality ended up better or worse than the dream?