What is the disadvantage of having 3 chambers versus 4 chambers of a frog?

Frogs with three chambers in their heart (two atria and one ventricle) have less efficient separation of oxygenated and deoxygenated blood compared to those with four chambers. This can lead to a mix of oxygen-rich and oxygen-poor blood, reducing the overall efficiency of oxygen delivery to tissues. Consequently, frogs with three chambers may experience lower metabolic rates and stamina compared to those with a four-chambered heart, which allows for better oxygenation and energy use.