It was supposed to have an underlying fiber composite structure so between the stainless-steel body and composite, there would be no rust problems. I think they ended up using steel and it ended up being overweight and underpowered.
What was interesting and which foreshadowed themes from the future, DeLorean first received some US government funding pitching it as a safety car and Ireland government money pitching it as a high-tech jobs program. Then the US government tried to entrap him. DeLorean beat the rap.
With a successful book and heavy publicity before his car came to market, John DeLorean himself had evolved into being more a celebrity than a credible businessman and engineer. In an era of economic and industrial stagnation, more than a few politicians and investors fell for his con.
Keep in mind that entrapment is a messy defense because it essentially admits to the crime -- for DeLorean it was cocaine trafficking -- but argues that the government created the opportunity and drew a vulnerable person into the trap. The defense succeeded but no one with money to invest would touch DeLorean after that because he was so obviously foolish, incompetent, and corruptible.