Here's hypothetical situation. Labour 28% Greens 16%, National 27%. The left's vote equals 44%. But Labour got more votes than National so in theory at least should be the predominant party to form a government. Compared with Labour gets 26%, the Greens 18%, National 27%. The Left's vote is still 44%, but National has more votes than Labour putting them in the best seat to form a new government. Party vote does matter between Labour and Green. Divide et impera - divide and conquer. The right understands this better than the left as a rule. Someone on Bluesky said something along the lines of, the right looks for allies, the left for traitors. A bit glib and facile for sure, but there is a germ of truth in that.