And I think there are plenty of people who aren't even consciously intending to scam. A while back I interviewed somebody for a 100%-time contracting position that will convert to employment. His LinkedIn listed him involved in a couple of other companies that he started. When I asked about this glaring incongruity he looked startled and said that, yes of course he was shutting those down. It felt to me like a lie made up on the spot.
He struck me as somebody who was just overextended and flailing around for immediate cash revenue. So I think he had convinced himself he could do his two companies and a full-time job. But I expect that in practice he'd stint us on hours and be so sleep-deprived during them that he'd be somewhere between marginally and negatively productive until we fired him.
But then it's hard to tell the difference between a desperate schmuck and a scammer, as I think it's a continuum. A lot of out-and-out scams get started like that.