Quote from: tonych on October 26, 2018, 12:07:25 AM

[...] PoW mining is an economic activity. You have capex, you have opex, almost all your profits are burned in your huge costs, and you have to care about efficiency in order to stay in the game. And in any economic activity, you have economy of scale. As your mining farm gets bigger, it becomes more efficient and stands better against the competition. You get volume discounts for miners, you will be the first in line for the new generation of miners, you can get cheaper electricity when you buy wholesale, it becomes worthwhile to relocate to a more favorable location, and you can hire the best talent in the industry. It doesn't matter if the PoW algorithm is ASICable or not, the economy of scale is universal. It might be not very important in the growing market when everyone, even a smaller and weaker miner, gets a portion of the growing pie, but nothing lasts forever and as the market matures and gets more competitive, the weaker players are darwinized, and the hash power gets concentrated in the hands of a few bigger miners. Miners, not mining pools. This looks like an end-game of any PoW based blockchain, because it has a heavy "hook" into the economy, and the economy favors scale. You can call it emergent centralization. Incidentally, Byteball moves in the opposite direction.

This is totally true and it should be engraved in stone, since Bitcoin evangelists seem so much in denial of that.
And even worse than this, PoW mining has also resulted to be totally unsustainable from an ecological point of view. Not only the waste of resources which heavy mining implies is basically nonsense, but it even could contribute to jeopardize human life on earth by accelerating global warming until it eventually spins out of control.
And that's not only me who is saying it. Please enjoy this article on the theme on prestigious magazine Nature:

https://www.nature.com/articles/s41558-018-0321-8.epdf

Byteball is much more likely than Bitcoin to spare human life on earth from extinction.
Not that this is necessarily auspicable, of course...