Then the customer will tell everyone that you have done poor work, and that they have proof of that, impacting your business negatively. It might be considered a form of fraud that hurts the consumer.

Sure, it is an half-truth that obscure what is really going on, but who ever corrects that, especially the MSM.

The ideal is that the artist will be truthful up front and will not accept work that he knows he can't fulfill adequately.