A business that only runs in one person’s head cannot be handed over, insured properly, sold, or left alone for two weeks. Written processes are what turn what you know into something the business owns.

It is also the quiet requirement behind a lot of other things. Hiring, a continuity plan, a compliance check, a buyer’s questions, an insurance claim after a loss: each of them asks, in its own way, for the same written description of how the work gets done.

Pick five processes, not twenty. The five you want are the ones that happen most often, or the ones that cost the most when they go wrong.

You are describing what actually happens, not what should happen. A document that describes the tidy version is worse than nothing, because people stop trusting it after the first mismatch.