I mentioned the financial aspect of a plan earlier, so let me add this. Another fact about financials to consider: not all business activities are about making money. Point being, in most enterprises financial considerations are centric to the document. But there are some other considerations. For example, a few years ago I wrote a plan for a new subsidiary that was focused on developing an inventory of patents. The potential financial returns were years into the future. Those patents may or may not ever have commercial value. Another example is a non_profit enterprise that has need for a complete roadmap for growing their profile in a market, of which a marketing plan would be the centerpiece.
What's more important, sales or profit? Profit is what generates your salary. You could actually make more profit with less sales. Less sales could actually be less work. The most important thing for a business is to make money. That's profit. Now some might say, I don't care so much about making a lot of money. I like the freedom of owning a business. Well that is probably true, but if you don't watch your profit, you might lose that freedom. It's always amazed me how most businesses, even very large ones, talk about how much their sales are. You hear comments like, that's a บꯠꯠ company. But what's a บꯠꯠ company if it has no profit. Now I do admit that 2% net profit of บꯠꯠ is a lot bigger than 2% of ũꯠꯠ but most likely the large one carries a lot more headaches too.