Banking run by humans has fundamental problems as well, that's why things like bitcoin come to existence. It is just a matter of tradeoffs.
AFAIK, most of the errors happen because users mistype the address or confuse the commission fee/amount fields, etc. UI could possible introduce some validations for fee/amount issue and probably require to retype the address or something else to avoid the other issue. Another issue is fraud, but it is a unavoidable product of such system, otherwise we end up with same problems traditional banking has. Fraud check means someone might deny the transaction even if your transaction is completely legit, for example, just because you are a citizen of a blacklisted country (my experience).
It is easy to dismiss bitcoin when you are a citizen of 1st world country -- because you are insider and have full privileges, but when you are outsider, it gets very complicated and things like bitcoin give some promise.