One word : Risk
Well its a lot of work. Basically monitoring and maintenance is kind of a 24/7 job. I only have a few miners and thats how it is to me. Of course i just minimize the risk change and if something happen during the night i just eat the loss, but if it was a bigger mining operation i'd need staff and such.
Personally i prefer just keeping it private.
Even hosting could get risky like you mention it not being private. It is one thing to fry your own gear but another thing to hurt someone elses.
It would be horrible to go to people who trusted you and say "Oops it got to hot now half of everything is fried". Sure that is a kinda worst case. But it could happen and I don't think to many insurance companies will want to have a hosting operation under them.
I see getting insurance to be kinda hard when they send someone out and see the sheer amount of electricity a commercial center hosting asics would need. Seems like it would be considered high risk with a pretty high premium if they take you as a client.
Indeed you would have to use a proper setup, starting your own hosting... service, to not say company is a lot of work as well. But for the end user, finding a trustable service for ASIC's machine should be possible. For instance i know there are a few around where i live, something like 75$/kW/Month.
Which is a bit expensive if you think about it considering it is possible to get 0.02/kW electricity here in a big industrial project.
I guess the real best way to do this is to run your machines at a friend who wont rip you off on the electricity cost.
But then again, you could run 2 S5 for 85$~ per month hosted here which is something like 50% fee/return.
Not sure if that's good for some users. Probably but ROI would be at around 1 year which is way too long imo.
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