If you advertise a problem as already solved and just needs fine tuning and sell stuff based on it and continue with the lie even after there are clear signals

If you advertise a problem as already solved and just needs fine tuning and sell stuff based on it and continue with the lie even after there are clear signals of it likely failing then I don't think then it's a failure _AND_ fraud. The fraudulent part is making absurd promised anyone with understanding of the topic knows you probably won't be able to keep. It is the part where you continue to push sells through this technology when it has shown to have problems. Being optimistic is grate, but lying is still lying and ignoring facts is still ignoring facts.