Updated wording to avoid ambiguity in default initial value behaviour. #4460

site/content/docs/01-component-format.md

@@ -42,7 +42,7 @@ Svelte uses the `export` keyword to mark a variable declaration as a *property*
 
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-You can specify an initial value for a prop. It will be used if the component's consumer doesn't specify the prop on the component. Note that whenever a specified prop is removed by the consumer, the value is set to `undefined` rather than the initial value.
+You can specify a default initial value for a prop. It will be used if the component's consumer doesn't specify the prop on the component (or if its initial value is `undefined`) when instantiating the component. Note that whenever a prop is removed by the consumer, its value is set to `undefined` rather than the initial value.
 
 In development mode (see the [compiler options](docs#svelte_compile)), a warning will be printed if no initial value is provided and the consumer does not specify a value. To squelch this warning, ensure that an initial value is specified, even if it is `undefined`.