I'm married to an orphan. That said, from his recounting of his years in the foster system (he was adopted at 13), I can see where a lot of people could have issues in their childhood and early adult life due to the abuses that many suffer at the hands of bad caretakers. This is not saying they're all bad, by any means, but there are certainly some bad ones out there. Of the people I know who were in the foster care system, the only one who is NOT doing well is the one who isn't an orphan -- she was removed from her mother's care as a child, and is now living in the same building as her mother. As soon as they were back together, the whole dysfunctional reality came raging back for her.
Life is what you make of it once you are able to choose for yourself, and whether someone uses their troubled past as an excuse to fail or a reason to succeed is up to them.