Rent-a-miner attacks seems to be another amusing example of when the existence of a market can break the system.
For example, voting works well in a democracy, but if we can sell votes, democracy would likely collapse because rich organizations would buy it up and control all politics. (Some say this is already true; but you know it would be way worse if votes were openly sellable).
Satoshi foresaw people trying to mount a 51% attack by buying a ton of machines, and so he went to great lengths to ensure this was unlikely using mining. I don't think Satoshi foresaw the liquid AWS-like market for instant hashing power. The ability to mount a limited-time 51% attack makes the attack literally 1000x easier than a buy-machine 51% attack.
It's bizarre to me that rent-a-miner is a viable business at all. Why don't the owners just set the miners to mine whatever the most profitable coin is at the moment?
The "owners" of the hardware are private miners. The rent-a-miner business (NiceHash) just connects sellers of hashrate (miners) with buyers of hashrate. The miners don't care what they are mining, and they get paid in BTC regardless of what their hardware actually mines. NiceHash is just a marketplace that automatically mines the most profitable coin by what people are willing to pay for hashrate. None of the hardware belongs to NiceHash.
Your question is still valid and good, but not in the way you have phrased it. The real answer is: laziness. NiceHash is easy and steady. If you have a nice gaming rig, you can make a few extra bucks a day by selling your hashing power while it's idle. If you are a serious miner, you probably don't use NiceHash.
Aren't the owners doing exactly that? Whatever is the most profitable coin is determined by the buyers of the rent-a-miner market and the sellers get paid that, less the cost to the market-maker for that discovery. How else could it be?
For example, voting works well in a democracy, but if we can sell votes, democracy would likely collapse because rich organizations would buy it up and control all politics. (Some say this is already true; but you know it would be way worse if votes were openly sellable).
Satoshi foresaw people trying to mount a 51% attack by buying a ton of machines, and so he went to great lengths to ensure this was unlikely using mining. I don't think Satoshi foresaw the liquid AWS-like market for instant hashing power. The ability to mount a limited-time 51% attack makes the attack literally 1000x easier than a buy-machine 51% attack.