Abilities that trigger "whenever players finish voting" trigger once all players have voted or once all secret votes are revealed, but they won't go on the stack until the current spell or ability finishes resolving.

In the case of non-secret voting, votes are cast in turn order, and each player will know the votes of players who voted beforehand.

Each player must vote for one of the available options. They can't abstain.

No player votes until the spell or ability resolves. Any responses to that spell or ability must be made without knowing the outcome of the vote.