Character ideas vs group compromise

[kyoryu]

Well then doesn't that just put my hoity-toity 'motivations are key to roleplaying' speech right in its place lol

Not really. It depends on the type of game you're playing.

In a fairly linear adventure that's mostly pre-planned, your motivations are basically irrelevant. You're gonna get on the train, so "chronic hero syndrome" is sufficient.

In a less linear game, your motivations will drive what happens, so they're important.