diff --git a/docs/core/entity/image.md b/docs/core/entity/image.md
index 61fb8e4d..44a37311 100644
--- a/docs/core/entity/image.md
+++ b/docs/core/entity/image.md
@@ -18,20 +18,22 @@ Properties should always only return information from memory and not do I/O (lik
 | Name               | Type                              | Default      | Description                                                                                              |
 | -------------------| --------------------------------- | ------------ | -------------------------------------------------------------------------------------------------------- |
 | content_type       | str                               | `image/jpeg` | The content-type of the image, set automatically if the image entity provides a URL.                     |
-| image_last_updated | <code>datetime.datetime &#124; None</code> | `None`       | Timestamp of when the image was last updated. Used to determine `state`. Frontend will refetch the image when this changes. |
+| image_last_updated | <code>datetime.datetime &#124; None</code> | `None`       | Timestamp of when the image was last updated. Used to determine `state`. Frontend will call `image` or `async_image` after this changes. |
 | image_url          | <code>str &#124; None</code>      | `UNDEFINED`  | Optional URL from where the image should be fetched.                                                     |
 
 ## Methods
 
 ### Image
 
-Implement `async_image` or `image` if your entity returns bytes of the image instead of providing a URL.
+Implement `async_image` or `image` if your entity returns bytes of the image instead of providing a URL. Frontend will call `async_image` or `image` to fetch the image. If the image is fetched remotely, image data should be cached and the cache invalidated when `image_last_updated` is changed.
 
 Note that:
 - The image entity's `async_image` or `image` method is only called when frontend fetches the image.
-- Frontend will only refetch the image when the image entity's state changes.
+- Frontend will:
+  - Fetch the image once when a page with an image entity is loaded
+  - Refetch the image when the image entity's state changed by the image entity changing `image_last_updated`
 
-This means it's incorrect to bump the `image_last_updated` property inside `async def async_image`. It should instead be done as part of a state update to signal that an updated image is available.
+This means it's incorrect to bump the `image_last_updated` property inside `async def async_image`. Instead, the image entity should, when an updated image is available or periodically if the image should be refetched after some time, update the `image_last_updated` timestamp. This can for example happen as part of an entity coordinator update.
 
 ```python
 class MyImage(ImageEntity):