What does that mean though? How can you possibly reapply a failed transaction later? The database itself can't possibly know how to reconcile that (if it did, it wouldn't have been a failure in the first place). So it has to be done by the application, and that isn't always possible. There is still always the possibility of unavoidable data loss.

"Consistency" is really easy, as it turns out, if you allow yourself to simply drop any inconvenient transactions at some arbitrary point in the future.