Multiplication Instead of Addition. If the components of a plan happen to be "times" one another instead of "plus" and one of the components is zero, then zero will be the result.
The Meaning of Plus. If you are adding the components, recognize that the process of adding may change the elements themselves. The sum may be more than a collection of ones.
Changing Value. The value of a component on one day or week will not be frozen. It will increase or decline over time.