In many cases, the text the reader can recover consists of only minor typographical corrections, but could also include a price quote, a critical clause in a contract, or something embarrassing. A cut/paste operation, or deletion of a large block of text, are each single changes, but could include a large amount of text.
To change the default settings from the WordPerfect menu, go to "Edit", "Undo/Redo History", "Options". From that screen you can change the number of corrections retained in the history or turn off retention of the history. This will erase the undo/redo history when the document is closed.
The good news is that this (I believe unique) feature can be helpful in recovering accidental deletions discovered after the file has been closed and reopened.