Did planning take the place of doing something, did good planning result in doing something successfully, or did inadequate planning result in a disaster?

DISCUSSION QUESTION, QUICK 500 WORD OR MORE ANSWER. WITH REFERENCES PLEASE

When your Course Developer was a boy, his mother had a canned response to his various ridiculous requests (e.g., a pony, when we were living in an apartment).  She would smile brightly and say, “Well, we’ll think about it.”  It took him years to discover that this actually meant, “We’ll think about it for ten seconds whenever you mention it, but it is NOT going to happen.”

This is a small instance of a larger truth.  Although a good plan is essential to a good project, planning can be an attractive alternative to actually doing something.  In Washington, as in industry, it’s common to “study a problem to death.”

Can you describe an instance from your own experience? Did planning take the place of doing something, did good planning result in doing something successfully, or did inadequate planning result in a disaster?  Explain.