[lexapro]

It's also non-trivial to guess a private key or to run a 51% attack.

[rurp]

Judging from empirical results it is quite easy to steal crypto currency; it happens all the time. I don't know why you only care about those two approaches.

[lexapro]

Because leaving Bitcoin on a hot wallet, which is the source of most of these hacks, is like leaving gold bars on a park bench.