Some secrets are shameful (like the ones I carried around for years). Some aren’t so much shameful as embarrassing (like that I can’t describe this Cheerios ad without crying). And some, we keep secret for the sheer pleasure of having a secret (like… oh, wait – I don’t want to tell you that one).
The iceberg principle applies to secrets: for every secret that comes out, ten (or a hundred) remain hidden. And still, information wants to be free. Not in the “costing nothing sense” – it doesn’t like being secret.
Over time, many (most?) secrets do come out.