Technology Trajectory Mapping
Visualize the collision course between what technology provides and what markets need
Trajectory mapping is Christensen's primary analytical tool for identifying disruptive threats and opportunities. A trajectory map plots two types of lines on a graph with time on the horizontal axis and performance on the vertical axis. The first set of lines represents the performance improvement that technologies provide over time, typically showing steep upward slopes driven by engineering progress. The second set of lines represents the performance improvement that markets demand over time, typically showing gentler upward slopes constrained by practical factors.
When the technology trajectory is steeper than the market demand trajectory, they will eventually intersect. Before intersection, the technology undersupplies the market's needs and cannot compete. After intersection, the technology oversupplies and triggers a shift in the basis of competition. This intersection point is where disruptive invasions become possible: the disruptive technology, which has been developing in a separate value network, crosses the threshold of minimum acceptable performance for the mainstream market.
The tool is powerful because it transforms abstract strategic questions into concrete, measurable comparisons. Rather than debating whether a technology will ever be good enough, managers can plot the data and let the trajectories speak. In the disk drive industry, trajectory maps predicted with remarkable accuracy when each generation of smaller drives would invade the next-larger market.
- The pace of technological progress almost always outstrips what markets demand, creating the conditions for disruption
- The intersection of technology supply and market demand trajectories marks the point at which a disruptive technology can invade a mainstream market
- Watch what customers do, not what they say, to accurately measure the market demand trajectory
- Trajectory maps for disruptive technologies must use different performance axes than those used for sustaining technologies, because disruption redefines what performance means
- Define the performance axesChoose the performance metrics that matter most in the mainstream market. For disk drives it was capacity; for excavators, bucket size; for electric vehicles, cruising range and acceleration. The vertical axis measures this performance; the horizontal axis measures time.Pro tipThe most important metric is usually the one that mainstream customers use to choose between products. But be prepared for the basis of competition to shift when oversupply occurs.WarningUsing the wrong metric will produce misleading trajectories. Make sure you measure what customers actually value, not what engineers think matters.
- Plot the market demand trajectoryMeasure the performance level demanded by customers over time. Use actual usage data rather than stated preferences. Plot the best-fit line through these data points. This line typically has a gentle upward slope constrained by practical factors in the customer's broader system of use.Pro tipMarket demand trajectories are often much flatter than technology trajectories. Traffic laws constrain how much acceleration drivers need, and commuting patterns limit how much range they need.
- Plot the technology supply trajectoriesPlot the performance of both the incumbent technology and the disruptive technology over time. The incumbent technology typically shows a steep upward curve. The disruptive technology starts lower but may have an equally steep or steeper improvement rate.Pro tipPlot the disruptive technology on the same axes as the mainstream demand trajectory, even though its initial value proposition is in a different value network. This reveals when the disruptive technology will become good enough for mainstream customers.
- Identify and interpret intersection pointsFind where the disruptive technology trajectory crosses the market demand trajectory. This intersection marks the approximate time when the disruptive technology becomes a viable competitive threat in the mainstream market. Before this point, mainstream customers cannot use it. After this point, they can, and the basis of competition shifts to favor the disruptive technology's other attributes.Pro tipThe intersection does not mean instant market takeover. It means the disruptive technology becomes good enough, at which point other attributes like price, convenience, and reliability begin to drive customer choice.WarningDo not assume that because the disruptive technology is worse than the incumbent technology at intersection, it will not win. Both cable excavators and 5.25-inch drives remained superior to their disruptive successors on mainstream metrics even after losing the market.
Christensen plotted the capacity provided by 14-inch, 8-inch, 5.25-inch, 3.5-inch, 2.5-inch, and 1.8-inch drives over time against the capacity demanded in mainframe, minicomputer, desktop, laptop, and notebook markets. The trajectories showed that each disruptive architecture initially fell far short of mainstream demands but improved at a rate that carried it into the mainstream market within a few years.
Christensen plotted electric vehicle cruising range and acceleration against mainstream market demand trajectories. Market demand for range was relatively flat (constrained by commuting patterns), while electric vehicle range was improving at 2-4 percent per year. The trajectories suggested intersection around 2015 for range and 2020 for acceleration.
Christensen created the trajectory map as the centerpiece of his disk drive industry analysis. By plotting the capacity provided by each generation of drive architecture against the capacity demanded in each tier of the computer market, he could visualize exactly when 5.25-inch drives became good enough for the minicomputer market, when 3.5-inch drives became good enough for desktops, and so on. He then validated the tool across excavators (plotting bucket capacity demanded versus supplied), steel (plotting quality requirements versus minimill capabilities), and electric vehicles (plotting range and acceleration demanded versus supplied).