Better is undefined until you say better for what; arguing which is better without a shared purpose is a disagreement about purposes.

The claim

Better is undefined until someone says better for what. Two people arguing over which product is better without a shared standard are not disagreeing about the product; they are applying different purposes, and no amount of evidence about features settles the argument until the purposes are stated. Once they are, the debate becomes a discussion of different needs, and both sides can be right. The example offered: a two-seat sports car is not better than a minivan for a family of six.