http://lm.i2p/nojs/knowledge/network-effect
When we look at this in the context of blockchain, and indeed commerce in general, the power of network effects quickly becomes evident. If Bitcoin is the crypto that most people know about, and is the one that most people buy, then more merchants will accept it. If more merchants accept it then there is more places to use it, so more people will buy it, and more people will know about it.