Fit the third one

Six dollars out is still six dollars out. Crank the weights again.

The two units doing the work here are cabernet and apricotty, so those are the two that move. Cabernet goes from 14.7 up to 18.4, apricotty from 23 up to 28.9, and the estimate lands on 30 exactly.

Three bottles, three perfect answers.

Except one of those two weights was not free to move.

Think back to the very first bottle, the cabernet that was mildly plummy and cost 22 dollars. The way that bottle was made exact was by setting cabernet and plummy to 14.7. That pair of numbers was the answer to bottle one. Nothing else recorded it.

The second bottle left them alone, because it was a viognier with no plum in it. Bottle one stayed safe.

This bottle is a cabernet. So cabernet has just been dragged from 14.7 up to 18.4, a rise of nearly 4 dollars, in order to suit a wine that costs 30.

Which means the number that was holding bottle one at exactly 22 is gone. It was overwritten a moment ago, to fix something else.

Bottle one has not been touched, tasted or mentioned. Its price has changed anyway.