mithrap
Ring a ding-ding, baby
-Well, Vic owes a lot to the hero, and it's quite clear that his business is on very fragile grounds, in a secluded little town whose only neighboors are slavers, drug addicts and tribals. Makes sense for him to walk out.-Vic at least can travel some time, to Vault City for example but he has his business to attend to in Klamath after all. And his info while not being plain helpful, does give at least a right direction.
-Marcus is a mayor of mining town with hard times when he needed the most even after the quest chain is over. It's over only for Tribal One, not Marcus!
-Cassidy without medical treatment won't last long normally.
-Myron getting all he need believes in speech of some tribal who rather belongs to the stables and goes away into anal enslavement treated worse than previous time, losing everything he had. He also should understand later that he's actually in danger walking around with the crew like hostile super mutant and another tribal.
-Goris senses something bad about his vault and go full "screw you, I'll go home." Alright, his revenge can be understood but it's way late in the game, let's be completely honest.
-Maria/Davin. Ha-ha, marriage business in Nevada, we get it. Ha!
-Sulik. Where his sister anyway? Shouldn't he politely abandon Chosen One after some time when he obviously does not searching his sister with this chosen jackass? (alright, fixed in Restoration Project, we can find his sister, yay, mods will fix it!)
-Skynet. Shouldn't his curiosity and autonomy also contribute to the decision of lefting Chosen Tribal alone, especially when core region is pretty much explored?
-Dogs. Dogs are dogs, no comments here.
-Lenny. While he does not have to leave, others should, seeing this one in the party, rather than just left tongue-in-cheek comments?
-Marcus cannot come with you until you succeed in quite a number of quests, to insure the short term stability of the town. He openly refuses to follow you until then, explaining why. As for his motivations, he is clearly an adventurer, like Harold. Not the kind of guys who will stay for long in a town. He'll follow you, like he followed others before (which led to lucrative opportunities) and like he'll follow others in the future.
-Cassidy doesn't plan on lasting long anyway. But rather than dying in a random bar fight, or in custody within the cells, he'd rather die in the open air, with a story to tell. He is bored out of his mind, and you have to push him in quite a long discussion before he finally goes "er, fuck it, let's do this."
-Myron leaves because of the choosen one's lies and false promises. Once he's out, he knows he can no longer go back to the Mordinos (they shoot him on sight, in the game). As far as we know, he is indeed knee deep in a journey he doesn't want to take part with, and he often complains.
-Considering how OP Goris is, it makes sense for him to fully join the hero late in the game. As for his motivations, they are a bit cheesy (knowledge, then revenge), but they kind of work.
-Sulik is a retarded tribal who couldn't walk one mile without getting caught by slavers, or getting in trouble again with racist locals. He has looked for his sister for a long, long time, so the choosen one is his best (only) option. Especially considering that they are both tribals. Makes sense that he trusts you, with or without the restoration mod.
-Couldn't say about Skynet, I never took it with me.
-Well, Lenny has his story about atonement, because he couldn't go with the hero's ancestor. He feels guilty about it and wishes to repair this youthful mistake, by helping you the best he can. As for the rest, the ghouls of Gecko seem to be quite nomadic. They settled not so long ago, accept strangers within their ranks, so it's safe to say that anybody can basically leave when they want.
Not sure what you mean. Some of these guy's motivations can be a bit simple, but none of them follow you blindly, without prior explanation on their motivations. Some of the longest dialogs of the game are the ones preceding the proposal of walking together, and hell, all can fail. If your karma is low, many won't follow you. Myron won't follow you if you aren't intelligent enough, or if you side with one particular family (if I remember correctly). Cassidy won't follow you if you're a slaver. Neither Sulik nor Goris will follow you if you have a low karma, I think. If you help the racists in Broken Hills, Marcus won't follow you.