It's not a revolving door decision. You can't vote-force your way into joining a separate country or political institution, e.g. Ukraine can't simply gain a majority vote to be part of the EU and it happens.

This is why it's seen as a once-in-a-generation vote. The impacts are so huge, revolutionary and so long-term, that it's not a conversation you want to have every 4-5 years until one year you chance your way to the preferred result.