Chaos. Disorder. Decay. In its general usage, entropy is a term in science that has to do with the tendency of things to become less organized over time. Like how, if you don't clean for a while, your garage will look like an IED went off in there. Or how two kids left unsupervised in a room will eventually start painting directly onto the furniture (even if they have to concoct their own paint out of fruit juice and paste).
In finance, it works much the same way. Entropy can act as a synonym to randomness. It means the unpredictability that exists in a market.
The notion applies to market leadership as well: It's hard to sustain dominance for very long, especially in the highly competitive technology world. Microsoft had a monopoly in operating systems (the things that run the guts of your computer). It viewed itself as the owner of desktops. Had it viewed itself as an integrator of global computing, it would have been a presence as a player on the internet. The entropy it took to keep its deep relevance was just too much for it to handle, and the company today is a shadow of its former self.
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