Disruptive Innovation Theory

Key Principle

Disruption is not a single phenomenon. It splits into two structurally distinct types:

New-market disruption competes against nonconsumption -- people who lacked the wealth, skill, or access to use existing solutions. The product only needs to beat doing nothing (or a crude workaround), not the incumbent's offering. Creates entirely new customers.
Low-end disruption targets the incumbent's most overserved, least profitable customers with a business model that makes money differently -- "lower prices but higher asset turnover, a different mix of sales and post-sales support revenue" (Ch. 1). Pulls existing customers downmarket.

Both exploit the same asymmetry: companies improve products faster than customers' needs evolve, systematically overshooting the mass market. Incumbents' values -- margin expectations, minimum deal size, cost structure -- make them unable to prioritize a response.

The basis of competition evolves in a predictable sequence: functionality, reliability, convenience, customization, price. Price-based competition appears last because "it is only after companies fulfill all customer needs that price becomes the only thing that matters" (Ch. 1).

Every market contains three customer tiers -- nonconsumers, undershot customers, overshot customers -- each signaling a different innovation opportunity. Misclassifying which tier dominates leads to the wrong strategy.

Why This Matters

Misidentifying the disruption type produces predictable failures:

Treating a new-market opportunity as sustaining: the product gets aimed at demanding existing customers who reject it for underperformance, instead of targeting nonconsumers who would accept it.
Treating a low-end disruption as a sustaining price war: incumbents cut price without changing the business model, destroying margin without gaining structural advantage.
Ignoring the customer-tier diagnosis entirely: "Identifying the industry circumstance is important because it defines what sorts of innovations will not flourish" (Ch. 1). A disruptive strategy in an undershot market, or a sustaining play for overshot customers, predicts failure.
The binding constraint on incumbent response is almost never resources -- it is values. "Incumbent firms fail in the face of disruptive innovations because their values will not prioritize disruptive innovations" (Introduction).

Good Examples

Telephone as new-market disruption (1870s): The telephone's limited range (a few miles) was irrelevant because it competed against nonconsumption in local communication -- it just had to be better than walking or not communicating at all. Targeting telegraph users would have failed because they needed long-distance capability the phone could not provide. (Ch. 1)
Steel minimills as low-end disruption: Nucor and other minimills targeted the least demanding steel products (rebar) that incumbents were happy to shed -- low margin, low quality requirements. The incumbent's rational neglect of unprofitable segments compounded until minimills climbed upmarket. (Introduction)
MCI Execunet as low-end disruption (1970s): MCI targeted price-sensitive business customers who did not need AT&T's full functionality. Customers dialed a 22-digit code. MCI built its own long-distance network while using AT&T's local lines -- a fundamentally different business model. (Ch. 1)
Fair Isaac credit scoring as rules-enabled disruption: Banking credit assessment evolved from expert intuitive judgment to codified scoring rules, enabling vertical disintegration. Companies "often unwittingly develop the rules that put their competition into business" (Ch. 1).

Counterpoints

Cramming disruption into sustaining markets: When customers are still undershot, integrated companies that control full system solutions earn above-average profits. "Specialist companies just don't control enough pieces of the puzzle to effectively commercialize radical sustaining innovations" (Ch. 1). Disruption aimed at undershot customers fails.
Competing against consumption instead of nonconsumption: New-market disruptors must target people who cannot use current solutions. Launching a simpler product at demanding existing users invites rejection on performance grounds. The telephone would have failed if marketed against the telegraph.
Confusing specialist displacement with disruption: Displacements enter at a point of modularity and target the mainstream market directly. "Unlike low-end disruptions that first target the least demanding customers, displacements first target the mainstream market" (Ch. 1). Treating displacement dynamics as disruption dynamics produces wrong predictions about who wins.
Assuming the entrant's cheaper product is disruptive: If the entrant simply offers a cheaper version of the same business model, it is not low-end disruption. The diagnostic signal is that the entrant's business model makes money in a fundamentally different way.

Key Quotes

"Incumbent firms master sustaining innovations because their values prioritize them, and their processes and resources are designed to tackle precisely those types of innovations. Incumbent firms fail in the face of disruptive innovations because their values will not prioritize disruptive innovations." (Introduction)

"Companies innovate faster than customers' lives change. In other words, what people are looking to get done remains remarkably consistent, but products always improve." (Ch. 1)

"Overshooting is the driver behind commoditization -- the process that results in companies being unable to profitably differentiate their products and services. If overshooting never occurred, products would never mature." (Ch. 1)

"New-market disruptive innovations tend to take a link out of this chain -- allowing people to do for themselves what previously required expertise." (Ch. 1)

Rules of Thumb