I remember 6 or 7-year-old me playing Smash64, thinking I'll just never know who the mysterious silhouette in the bottom left corner was. Until, that is, when I visited a friend who had the game and saw that it was some creepy looking kid with beady, soulless eyes and a yo-yo. I excitedly asked "How did you unlock him?!" to which he responded "I don't remember."
Anyway, now that the internet is such a big thing now (waaay bigger than then anyhow), I don't really see what the point of "secret" characters is any more... or secret anything for that matter. The novelty of unlocking hidden content reeaally wears off pretty much the day after release.
I mean, I don't mind or anything. I'm just curious what the reasoning behind it is, or how it's decided who's a starter and who isn't. Like it was mentioned, Ness was a starter in Melee...