When duplicating or copying an item in Sitecore, all the versions are copied to the new item as well. Sometimes this is unwanted behaviour, especially when the first version of the item was not part of the workflow. When you publish the item, the latest published state would be published (i.e. the non-workflow version)
A simple trick is to remove the previous versions of the item when duplicating or copying item. This is done by intercepting the uiCopyItems and uiDuplicateItem.
Note that for uiDuplicateItem, the Sitecore.Buckets.config aborts the pipeline before the original duplicate pipeline. To avoid this, we make sure our custom pipeline is triggered first before the bucket config.
Custom config patch:
Then we have a Sitecore extension helper to remove the previous versions:
And that's it. Note that I applied this to Sitecore 7.2 Update 5