This problem seems like it could have been fixed by a better UI though, specifically one which included a confirmation step that showed the implications of the

This problem seems like it could have been fixed by a better UI though, specifically one which included a confirmation step that showed the implications of the decision i.e. the amounts that would be transferred and who they would be transferred to. If there was a screen that said "the transaction you have selected will result in a total of $900 million being sent to the following parties, broken down as follows: ...; Please confirm you wish to proceed" - then the outcome would have been very different.