During a fundamental technology shift like the current AI wave, traditional market size analysis is pointless because new markets and behaviors are being created. Investors should de-emphasize TAM and instead bet on founders who have a clear, convicted vision for how the world will change.

Contrary to the belief that new form factors like phones replace laptops, the reality is more nuanced. New devices cause specific tasks to move to the most appropriate platform. Laptops didn't die; they became better at complex tasks, while simpler jobs moved to phones. The same will happen with wearables and AI.

Unlike mobile or internet shifts that created openings for startups, AI is an "accelerating technology." Large companies can integrate it quickly, closing the competitive window for new entrants much faster than in previous platform shifts. The moat is no longer product execution but customer insight.

Traditional market sizing, which analyzes existing demand, is useless for true technological breakthroughs. A fundamental change on the supply side (e.g., GPUs for AI, cloud for software) unlocks markets that are orders of magnitude larger than their predecessors (e.g., gaming, on-prem software).

Analysts often mistakenly constrain a disruptor's potential to the size of the existing market it's replacing (e.g., valuing Uber based on the taxi market). Truly disruptive products create entirely new behaviors and expand the total addressable market (TAM) by orders of magnitude, a key insight for valuing high-growth companies.

The narrative of startups "destroying" incumbents is often wrong. As shown by MongoDB coexisting with Oracle and HubSpot with Salesforce, disruptive companies can create massive value by expanding the total market, allowing both new and old players to grow simultaneously.

The narrative that AI will immediately and negatively disrupt all software companies is flawed. Significant infrastructure capex is required before widespread adoption, delaying the impact. Furthermore, many well-positioned incumbent software companies will actually benefit from AI, using it to expand their margins.

Companies like Amazon (from books to cloud) and Intuitive Surgical (from one specific surgery to many) became massive winners by creating new markets, not just conquering existing ones. Investors should prioritize businesses with the innovative capacity to expand their TAM, as initial market sizes are often misleadingly small.

Consumer innovation arrives in predictable waves after major technological shifts. The browser created Amazon and eBay; mobile created Uber and Instagram. The current AI platform shift is creating the same conditions for a new, massive wave of consumer technology companies.