Ask HN: How do things actually get 'leaked'?

How do things such as (recently) TV show episodes [1] [2] or celebrity personal media get 'leaked'? Other examples include movie release info/trailers [3] or new smartphones, OS, or tech related info. I am excluding being hacked as a reason for data to be exposed. I am actually curious about the procedure of how (presumably) someone on the inside gets access (especially digitally) and is able to distribute it without being caught. How does the information spread? Moreover, if caught, what would the potential consequences be? For case of TV shows/etc., what if the 'leak' caused an increase in ratings or maintain hype? All of the following would heavily hinder the ability to reveal insider info (especially anonymously). Security cameras, digital footprint, access logs/timestamps, locked doors/computers, logins, NDAs, etc. (what are some other things one would have to bypass?). For that reason, I suspect that most leaks are done intentionally and methodically for one's own benefit (at least in the case of TV show leaks, or documents/trailer leaks regarding movies) since it seems very difficult to circumvent the previously mentioned obstacles. Saying it was leaked could be an interesting way to actually reveal certain announcements (seemingly prematurely to the unsuspecting audience). Obviously, this question and discussion is relevant to any kind of revelation of insider information (including government, military, and tech sector), but I was specifically interested in media and television. It seems like a strange phenomenon to me and would love some insight. [1] http://www.hypable.com/2014/06/08/early-episodes-of-the-legend-of-korra-season-3-leak-online/ [2] http://www.mirror.co.uk/tv/tv-news/flash-pilot-leaks-reviews-fans-3768103 [3] http://wegotthiscovered.com/movies/kevin-smith-dc-warner-brothers-plan/