Vanguard, IGN has published an interview with creator Brad McQuaid that might pique your curiosity. There are some interesting nuggets relating to McQuaid's early days as well as the relationship between Sigil and SOE that allowed Vanguard to release, albeit in an early and extremely buggy state.
"The game sold very well at retail. Around 250,000 units just blew out of the stores. But the game wasn't optimized, the client wasn't optimized, and the server wasn't optimized," McQuaid explains. "The vast majority of people who played it early on left by the time their characters hit level two or three."