The Law of Diffusion of Innovation depends upon the "tipping point" for capturing a market and relies upon the division of the general market place into categories ranging from Innovators to Laggards. This law states that for a product to capture the middle 68 percent of the general market place, a 15-18 percent share must be captured as this quantity of purchasers will "tip" the innovation into the mid-section of the market place where people buy only because someone else bought first.
More specifically and as Sinek explains, the first 2.5 percent of the general marketplace and general population comprises the innovators of new ideas. The next 13.5 percent comprises the early adopters of new innovations. The next 34 percent comprises the early majority while the following 34 percent comprises the late majority. The last 16 percent comprises the laggards who only buy new innovations because the new innovations have displaced the existing technology: "the only reason these people buy touch tone phones is because you can't buy rotary anymore" (Simon Sinek, TED Lecture).
This law is important in advancing new ideas because it explains and identifies precisely how commercially successful an innovative product or concept must be for it to be spread amongst the majority of the populace and the general market place, in other words, for it to be purchased by a large enough market share for it to capture a profitable market.