Further to Corinne's point, although metadata is very important to everybody who thinks that their goal is to provide metadata, especially from the public sector, many jurisdictions have developed their own approach to metadata.
If you're a user of open data or a developer, chances are you're going to want to bring data in from more than one jurisdiction. If we're all using different metadata, it can make that very complicated for the individual user.
Our goal is to work with other jurisdictions to map our metadata against each other in order to be able to provide potential users with easy-to-use tools that will make the data from different places more interoperable, more comparable to each other.