If you only show up to tell us you don't need a stinkin' guild, that's fine. That's what we're here for
If you leave for another guild, no hard feelings (unless you otherwise incited hard feelings, in which case we're happy to see you go.) In other words, we're not your mommy or spouse, you can come and go as you please.
If you left another guild on bad terms, we don't discriminate because we don't care. If you want to badmouth them, feel free, but don't expect any sympathy, because that's what you get for joining a Guild.