Vault Workgroup, Collaboration, and Manufacturing provide configurable lifecycle definitions and states to follow your company's processes. During the design process users can create a number of file versions in Vault through check in/out, and these have rules around purging out excess data in what's referred to as a 'series'. The Vault ships with predefined lifecycle states, definitions, and purge rules, and this should be used as a start point, but you can modify these as necessary.
For the examples below, I enabled the 'Show all versions' option in the History window and turned on the Version column, sorted descending.
For each State, there are four options on purge control: All, First and Last, Last, and None.
All: Used by default for the 'Released' state, every version will be maintained when a Purge is performed.
First and Last: The default for all other states, this option will keep the first and last version in a series.
None: With this option for this state, no record of the file will exist after the purge is performed.
The final screen displays the results of the Purge. Per the Control rules on the Work In Progress state in our example lifecycle definition, versions 2,3,4 are removed while versions 1 and 5 are maintained.
Depending your workflows, you may also opt to change the Purge Control on the Work in Progress (WIP) and Quick Change states to 'Last'. As these are widely used and popular editing states, changing this will reduce the versions to the last one right before the next state change.
The Released state contains an option for declaring that its a 'Released' state. While you can change the name, this contains functionality to protect files in that state, and it disables the 'None' option to ensure these versions are maintained and never purged out.
As an Administrator, be sure to run through examples on your data and determine which purge option is best for your users or company.