Because miners physically compete to establish dominance over ledger writing authority. Worth noting physical power competition is highly egalitarian, noble, and virtuous. Especially when it's non-lethal like Bitcoin is.
yea. I'm following. at least in think. but I see struggle in everything. (except abiding, dude). I mean, right down to the constant struggle of your immune system to fend off infection or the constant struggle of life itself to maintain itself against the increasing entropy of the universe. hierarchy and struggle is literally life. oh now you did it. now you got me thinking.