[davidw]

In economics, this is an information asymmetry problem if I'm not mistaken:

http://en.wikipedia.org/wiki/Information_asymmetry

In other words, the people selling the bitcoin services know more about their own security than users do.

[stanleydrew]

Yes, but it is a little different than the traditional used car "lemon" information asymmetry problem, since there is an ongoing relationship and the reputation effects are much stronger.