innovation s-curve and diffusion of innovation

Two connected frameworks explain how technologies spread and why companies built on them get disrupted: the innovation S-curve and Rogers' diffusion of innovation theory. Together, they give PMs a lens for thinking about where a technology or product sits in its lifecycle — and what comes next.

The innovation S-curve

Every technology follows an S-shaped performance trajectory over time:

Emergence phase (the bottom of the S): Initial development. Performance improves slowly. Investment is high, returns are low. Only enthusiasts and researchers engage with it. The technology is expensive, fragile, and limited.

Growth phase (the steep middle of the S): A breakthrough unlocks rapid performance improvement. Investment accelerates. The technology crosses from niche to mainstream. This is the period of maximum disruption — existing technologies can suddenly seem obsolete.

Maturity phase (the top of the S): Performance improvements slow. The technology approaches its physical or conceptual limits. Further investment yields diminishing returns. The technology is now commoditized or embedded.

The critical moment for incumbents is not the emergence phase — they can ignore emerging technologies that are too limited to threaten them. The dangerous moment is the transition from emergence to growth: the point where the new S-curve starts its steep ascent while the old technology is still at its maturity plateau.

At this transition, incumbents have three options:

1. Ride the new S-curve by investing in the new technology (Amazon and AWS; Netflix transitioning from DVD to streaming).
2. Acquire the new S-curve by buying the disruptor early (Facebook acquiring Instagram; Google acquiring YouTube).
3. Ignore the transition and be overtaken (Kodak and digital photography; Blockbuster and streaming).

Rogers' diffusion of innovation

Everett Rogers mapped how new ideas and technologies spread through social systems. His five adopter categories describe the pace of adoption across a population:

Innovators (2.5%): First to adopt. Motivated by the technology itself. Willing to accept failure. Provide technical feedback that helps refine the innovation. Essential for getting early traction but not representative of the mainstream.

Early Adopters (13.5%): Opinion leaders. They adopt early, get results, and communicate those results to peers. The key gatekeepers between the innovation and the mainstream. This is where social proof begins.

Early Majority (34%): Wait for social proof before adopting. They follow early adopters' recommendations. They represent the beginning of mainstream acceptance. Crossing the threshold from early adopters to early majority is the Chasm — the most difficult phase in diffusion.

Late Majority (34%): Skeptical. Adopt primarily because of peer pressure or when alternatives disappear. Price-sensitive. Do not lead; follow. Represent the second half of mainstream adoption.

Laggards (16%): Resistant to change. Adopt only when forced or when the alternative is entirely unavailable. Sometimes hold valuable institutional knowledge about why existing systems work the way they do, which can be useful input for the next innovation cycle.

The connection: S-curve transition and chasm crossing

The S-curve and Rogers' diffusion theory describe the same phenomenon from different angles.

When a technology transitions from the emergence phase to the growth phase of its S-curve, it is simultaneously crossing from innovators and early adopters to the early majority. The Chasm in Rogers' framework corresponds to the inflection point at the bottom of the steep S.

This is why crossing the Chasm is hard: the technology may have genuine advantages for innovators and early adopters (who tolerate limitations), but the early majority needs the complete solution. The technology needs to be not just better in some dimension — it needs to be reliable, integrated, supported, and clearly better in the ways that matter to a risk-averse pragmatist.

Practical implications for PMs

Reading the S-curve for your technology: Where does the technology your product is built on sit? Is it in the steep growth phase (rapid improvement, window of opportunity) or the mature plateau (incremental gains, commoditization ahead)?

Reading your product's adoption curve: Which adopter category are your current users in? If they are mostly innovators and early adopters, you are still pre-Chasm. The product and go-to-market strategy required to cross the Chasm is different from what got you to early adopters.

The AI context (2024-2026): Large language models and generative AI are currently in the steep growth phase of their S-curve. The transition from emergence to growth happened roughly 2022-2023. PMs building on AI are building during the window of maximum disruption — but also maximum uncertainty about where the S-curve plateaus. The early adopters are already using AI products. The crossing to the early majority is happening now, and it requires the complete solution (reliability, accuracy, integration, privacy) that innovators tolerated without.

Multiple S-curves in parallel: Modern products often combine multiple technologies, each at a different point on their S-curve. Your mobile app may be built on a mature mobile OS (mature S-curve) but uses AI features still on the steep growth phase. Managing these different maturity levels simultaneously — being stable and reliable where users expect it, and aggressively innovative where the new S-curve is steepening — is one of the PM's ongoing challenges.