Referring to this thread , there are corporations that mass spam new players with invites to join their ranks, just to milk them.
A layer to hopefully protect a new player to join such a rogue corporation, could be a notification window that pops up as soon as the player wants to leave the starter corporation and that warns him that he’s now on his own.
It’s just a one time popup and everybody should be warned enough and happy afterwards.
Given that you can always return to an NPC corp, which for all intents and purposes is equivalent to the starter corp (though not the starter corp itself), this is not necessary since it is always there to provide a “safe home corp” free of potential player ■■■■■■■■. (Though really, if you want to lone wolf for whatever obscure reason in an MMO, you could always create your own tax haven corp.)