Proper preparation prevents poor performance.
Poor planning or poor execution of plans is simply to let some force other than reason shape reality.
But amid much elegance and precision, the details of life and the Universe also exhibit haphazard, jury-rigged arrangements and much poor planning. What shall we make of this: an edifice abandoned early in construction by the architect?
He who fails to plan, plans to fail.
Many people spend more time in planning the wedding than they do in planning the marriage.