Diamond discusses this concept in chapter 13. An autocatalytic process, he says, is "one that speeds up at a rate that increases with time, because the process catalyzes itself." The reason this happens is that technology builds upon itself, in other words, one invention depends on many others. Gutenberg's printing press, for example, depended on several other inventions, including a screw-press used primarily to make olive oil and wine, as well as innovations in paper-making. When we view the development of technology historically, then, we see that in a very real sense, it provides its own momentum. The more technology a society has, the more it can develop. This property of technology, as we might call it, was yet another advantage enjoyed by Eurasian societies, because they developed important technologies earlier due to a number of geographical advantages.
Source: Diamond, Guns, Germs, and Steel, 258-260.
The term "autocatalytic process" is taken from chemistry and technically means that at least one product from a reaction is one of the reactants used in the process. It is a type of "self-sustaining" process. A humanistic equivalent to this term is "virtuous circle" or "virtuous cycle," in which there is some form of positive feedback loop.
Jared Diamond, in Chapter 13 of Guns, Germs, and Steel, uses this concept to explain how certain technologies cause civilizations to develop at an exponential rate, making it difficult for societies that develop technologies later to catch up.
For example, a society the domesticates animals has a more regular and efficient source of food and transportation than one that does not domesticate animals. This allows the society to settle in one place and invest in intensive irrigation and farming. This leads to increased population, allowing for the creation of a greater food surplus. Development of metallurgy allows people to create better tools, which in turn makes them better at metal working and mining. Many technologies have this sort of autocatalytic effect according to Diamond.