If you don't believe in your product, or if you're not consistent and regular in the way you promote it, the odds of succeeding go way down. The primary function of the marketing plan is to ensure that you have the resources and the wherewithal to do what it takes to make your product work.

The Guerrilla Marketing Handbook (ed. Houghton Mifflin Harcourt, 1994) - ISBN: 9780395700136