Illustrative example
A couple buy a house without an agent of their own. Nobody mentions a disclosure statement at any stage, and they first hear of it months after the closing.
Where a buyer is unrepresented, the duty to inform them of their rights and obligations under the article falls on the seller's agent who is dealing with them, and it must be performed before the buyer signs a binding contract of sale. So the fact that decides it is whether anyone explained the article before signature - not whether the buyer had representation of their own.
The brokerage contributes towards the repairs and adopts a written checklist so that unrepresented buyers get the explanation at the first viewing rather than not at all.