Explanation:

- Liquidity Ratios: These measure a firm's ability to meet short-term obligations. They are crucial for understanding the firm's financial health in the near future but not over the long run.

- Activity Ratios: These assess how effectively a company utilizes its assets. While important for operational efficiency, they don't directly address long-term sustainability.

- Solvency Ratios: These evaluate a firm's ability to meet long-term obligations and ensure the firm's survival. They provide critical insights into the long-run operation of the firm.

- Profitability Ratios: These measure a firm's ability to generate earnings relative to sales, assets, and equity. They focus on the firm's success but not on its long-term viability.