Sustained economic growth refers to the ability of an economy to consistently increase its output of goods and services over a long period. This continuous growth is crucial as it indicates improvements in productivity, living standards, and the overall health of the economy, allowing for more jobs and better wages. It is often represented by an upward-sloping Long-Run Aggregate Supply (LRAS) curve, which reflects a stable increase in potential output due to factors like technological advancements and increases in capital and labor resources.