Planning for success
I've sometimes joined that exhortation but it isn't long since I told my co-author of Success in Store: How to Start or Buy a Retail Business, Enjoy Running It and Make Money that I've never had a business plan.
He then took me through how I'd started a couple of businesses, and justified his own "always have a business plan" position. He claimed I'd had quite a detailed plan in each instance -- it was just that I had not written it down! So, as a writer, the one thing I've never written down, is my plan for success. However, more of those businesses have gone according to plan than those which have not.
The one example when you will need a formal plan is if you are going to borrow money. However, even then a business plan can be drawn up on the back of an envelope.
A very nice restaurant I go to occasionally has paper tablecloths and marker pens in a glass on every table because the owner says her original business plan was drawn up over a meal in another restaurant and she had to appeal to the manager of that restaurant for some paper to write it down.
It also helps to include, in advance, what you will consider to be failure. ("I will have failed if I do not publish two books in the first six months, sell 1000 copies or not be within a few hundred dollars of breaking even in the second six months").
Too many people struggle on because they attempt to justify the changed cicumstances.
There's no reason why a "business" plan can't be that within 12 months "I will have published Uncle Joe's memoir, sold 20 copies and he'd added me to his will".
You could probably carry that one in your head.

