They are parked for various reasons.

• We haven't planned what to do with them yet.
• We know exactly what we want to do with them, but it will require more work than we can justify at the moment -- given the cost/benefit predictions
• We are in the process of rethinking what to do with the site.
• We are waiting for the proper "helper" to come on line to work with us on the site.
• We just felt like parking the site.
• It was a horrible mistake, and we didn't really mean to park it.