Michael Porter (Harvard Business School) published a model in 1979 explaining why some industries are structurally more profitable than others. Five forces determine an industry's attractiveness — not a company's.
The five classic forces:
- Rivalry among existing competitors
- Threat of new entrants
- Threat of substitutes
- Bargaining power of suppliers
- Bargaining power of buyers
The stronger these work against you, the harder it is to make money in the industry — regardless of your own strategy.
What has changed with AI
Two forces have changed materially:
Threat of new entrants — grown radically
Previously, entering most markets required capital, team, infrastructure. Now a solo founder can build a competing product in a week with AI.
This means: nearly every industry suffers from a growing new entrant threat. Industries that were defensible through capital requirements are now wide open.
Substitutes — grown
Same logic: when AI makes building one product fast, it also makes building totally different substitute solutions fast. Your text-based tool can suddenly be replaced by a voice or visual version you didn't see coming.
Buyer power — grown
Customers see comparison prices in seconds. Alternatives are always at fingertips. Loyalty requires more than ever.
Supplier power — depends
AI models have a limited number of major suppliers (Anthropic, OpenAI, Google). That gives them bargaining power. But: competition among suppliers is fierce, and open models (Llama, etc.) add options.
Rivalry — intensified
Combine increased entrant threat + increased buyer power + sharing the same AI layer with competitors = competition is exceptionally hard.
What this means for strategy
Classic Porter playbooks suggested: "find a structurally attractive industry" or "build a strong position on one of the five forces." Still valid, but priorities shift.
Strongest defenses in the AI era:
- Network effects (product value grows with more users)
- Switching costs (hard for customers to leave, e.g., due to integrations)
- Brand with a community (loyalty that doesn't break when competitor cuts price)
- Access to rare data (proprietary data making the product better over time)
- Execution speed (competitors can't follow)
What doesn't work alone anymore:
- Pricing (customers compare in a second)
- Functional features (AI-copyable)
- Advertising (expensive, noise war)
How AI helps in Porter analysis
Use AI for industry structure analysis:
"I'm in [industry]. Walk through the five forces. For each: rate the strength (low/medium/high), reasoning, and one concrete example from this industry."
Then go deeper:
"In my industry, new entrant threat is high. What three defense strategies are realistic for an early-stage founder?"
AI generates options, but you decide which is possible for you.
Practical workflow
- Define your industry tightly (not "SaaS", but "AI-assisted founding-stage tools for Nordic first-time founders")
- Walk the five forces with AI
- Identify the 1–2 strongest threats
- Plan defense against them
- Re-walk quarterly
Closing
Five Forces doesn't tell you whether you'll win — it tells you whether the playing field favors you. AI has changed the playing field: one force (new entrant threat) has grown across nearly every industry, and only a few defenses still work.
Start: do a Five Forces analysis of your industry in 30 minutes with AI. Decide one concrete action that strengthens your defense against the strongest threat.