A substantive advantage of the liquidity framework proposed by the Basel Committee is its ability to improve the management of liquidity risk, which is inherently a cash flow risk and cannot be fully addressed via liquidity-based capital requirements only.
The chosen option directly gears both the assets and liability mix towards, respectively, higher liquidity and more structural (longer-term) composition, also providing observable and verifiable metrics for the purposes of rigorous monitoring. By doing so, it explicitly promotes prudent liquidity risk management, thus minimising the likelihood of unexpected liquidity shortages, which may be covered only at prohibitively high cost at times of distress.