All of those things can be mitigated by other traits. Connections can be useful even without very much charisma. Cleverness can lead to pretty good earning potential even with relatively little conscientiousness, and may help one think of ways to improve charisma and conscientiousness. At any given level of earning potential, being cheap ("frugal" would be a better word but begins with the wrong letter) eases the transition from gradually sliding into debt to gradually accumulating savings. Other aspects of character besides conscientiousness make a difference -- e.g., a reputation for honesty may be helpful.

Given a bad enough deficit in everything that matters, it's certainly possible to be so screwed that recovery is unlikely. It's also possible to overestimate those deficits and the resulting screwage, e.g. on account of depression. There's probably a nasty positive feedback loop where doing so makes getting unscrewed harder.