The Wiener index W(G) of a graph G is the sum of distances between all unordered pairs of its vertices. Dobrynin and Mel'nikov [in: Distance in Molecular Graphs - Theory, 2012, p. 85-121] propose the study of estimates for extremal values of the ratio R_k(G) = W(L^k(G))/W(G) where L^k(G) denotes the k-th iterated line graph of G. Hriňáková, Knor and Škrekovski [Art Discrete Appl. Math. 1 (2018) #P1.09] prove that for each k>2, the path P_n has the smallest value of the ratio R_k among all trees of large order n, and they conjecture that the same holds for the case k=2. We give a counterexample of every order n>21 to this conjecture.