In the second half of 2025, excess liquidity has been cited as a key driver of the depreciation of the Korean won and rising asset prices, based on Korea’s relatively high money-to-GDP ratio (Marshall’s k). However, since Marshall’s k is the inverse of velocity, this claim effectively restates that velocity is structurally low. Applying Benati's (2020) velocity–natural rate of interest framework to Korean M2 data, this study identifies the structural determinants of the secular decline in velocity, thereby providing an academic response to the excess liquidity debate. The results show that the potential growth rate, as a long-run determinant of velocity, exhibits markedly greater explanatory power than the policy rate, a finding that holds consistently for M1 velocity and across a range of robustness checks. These empirical results suggest that Korea's M2 growth reflects a normal money demand response accompanying the decline in potential growth rather than excess liquidity, and that the fundamental remedy for sluggish monetary circulation lies not in monetary policy but in raising the potential growth rate.