Why are most rivers in Keralam short and swift-flowing?

Most rivers in Keralam are short and swift-flowing primarily due to the state's unique topography, which is dominated by the Western Ghats.12

These mountains rise abruptly from the narrow coastal plain along the Arabian Sea, creating steep seaward slopes. Because the distance between the high-altitude origins of these rivers in the Western Ghats and the coast is relatively small, the rivers have short courses. The steep gradient of the terrain forces the water to move rapidly toward the sea. Additionally, these rivers are heavily dependent on the monsoon rains, which provide the necessary volume to sustain their flow through the landscape.341