* Rain shadows are a local phenomenon: They occur when mountains or other elevated terrain block moisture-laden winds from reaching one side, creating a dry area on the leeward side. This is a localized effect, not a global pattern.

* Wind patterns are complex: Global wind patterns are driven by a combination of factors like the Earth's rotation, uneven heating, and land-sea contrasts. These create complex circulation patterns, not simple circular belts.

* Mountain ranges vary: Mountain ranges are not evenly distributed across the globe, and their orientation varies. This means rain shadows occur in specific locations, not in a uniform circular pattern.

Here's an analogy: Imagine a wall blocking wind from reaching a garden. The side of the garden behind the wall will be drier (like a rain shadow). This doesn't mean the wind blows in a circle around the garden, it just means the wall creates a localized area of dryness.

To summarize: Rain shadows are localized effects caused by specific geographic features, not a global pattern. Global wind patterns are much more complex and cannot be simplified to circular belts.