Before anything else: who is in this market, what are they currently doing, and why does that leave room for you?
A market is not a category on a slide. It is a set of people with a shared problem and an existing way of coping with it. If you cannot describe the coping mechanism you are competing against — usually a spreadsheet, an intern, or doing nothing — you do not understand the market yet.
In practice: Makerz Network
Makerz Network sized its own market as three nested numbers rather than one.
- Total addressable — over 100 million professional service employees worldwide.
- Serviceable — 17 million of those sit in management, scientific and technical consulting.
- Obtainable — roughly 850,000 people hold a product management job today.
Each figure came from a different published source, and each is a narrower claim than the one above it. The useful number is not the top one. It is the bottom one, which is small enough that you can name the people inside it and go and find them. A market you can only describe in hundreds of millions is a market you have not finished thinking about.