A significant challenge in estimating modal parameters from output-only data is the greater uncertainty in damping ratios compared to natural frequencies. Despite its importance, limited theoretical work has been dedicated to understanding this issue. This study presents key findings derived from the application of random vibration theory to the estimation of damping ratios and natural frequencies. The results offer new insights into the factors affecting the accuracy of these estimates and emphasize the need for further investigation to enhance the precision of modal parameter identification in dynamic systems.