Here's why:

* Venus is extremely hot and dry: Its surface temperature is over 460°C (860°F), far too hot for liquid water to exist stably.

* No liquid water on the surface: While some scientists theorize that Venus may have had oceans in the past, its current atmosphere is incredibly dense and composed mostly of carbon dioxide, creating a runaway greenhouse effect that traps heat.

* Volcanic activity: Venus is volcanically active, but its eruptions are thought to be primarily of lava flows, not water-based floods.

However, there is evidence of past water activity on Venus.

* Some geological features: Certain geological features on Venus, such as channels and possible ancient riverbeds, suggest that liquid water may have existed on the surface in the distant past.

* Atmospheric composition: The presence of deuterium in the Venusian atmosphere, a heavier form of hydrogen, suggests that some water was lost from the planet over time.

While Venus doesn't have flood plains today, its geological history suggests that water may have played a significant role in its past.