A list of values cannot have an initial value. You can either set the initial value to the textitem the lov is assigned to, or if you are talking about a listitem, to that listitem. For both textitems and listitems you have different choices for a initial value
1. A hardcoded value put directly in the property initial value
2. A block.item's value, which you can set at runtime
3. Any assignment in a WHEN-CREATE-RECORD-trigger at the block.