Limiting the metadata available in your feed helps reduce the RSS feed size. This is a helpful option if you are using a feed proxy such as Feedburner which limits the size of your feed.
Please note that when limiting the number of episodes, the number added to Publish coincides with the latest published episodes. For example, if you limit your metadata to 10 episodes, the newest 10 episodes will contain all metatdata and the rest of your episodes will be trimmed.
By selecting this option you are trimming the following metadata from your episodes: