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.
Next you will need to carefully examine what actually goes into your offering. How many hours does it take to create those one_of_a_kind bracelets? How much does it cost to bake a dozen of your special recipe cookies? How much research goes into "whipping up" a website? Making tangible goods requires space. Do you have room to grow enough squash to actually generate profits? Are these numbers you could sustain beyond the occasional personal or family use of your product or service? The business planning process can be very helpful to "accidental entrepreneurs" as it allows you to decide which ideas are best left as hobbies and which ones could provide some real cash flow.