Folklore: The manager is a reflective, systematic planner
We have this common image of the manager, especially in a senior job, sitting at his desk, thinking grand thoughts, making great decisions, and, above all, systematically planning out the future. There is a good deal of evidence about this, but not a shred of it supports this image.
Facts: Study after study has shown that (a) managers work at an unrelenting pace; (b) their activities are typically characterized by brevity, variety, fragmentation, and discontinuity; and (c) they are strongly oriented to action.
...managing is just one damn thing after another.
From Managing, by Henry Mintzberg.