Build a TAM/SAM/SOM estimate with sourced assumptions, bottom-up math preferred over top-down, and a pessimistic/base/optimistic sensitivity table. Use when the user asks "how big is this market", "TAM for my pitch deck", "size the opportunity", "is this market big enough", or needs SAM/SOM numbers investors will probe. Don't use for dissecting a single rival's product — that's competitor-teardown — or for weekly market monitoring — that's trend-radar.
