Amir is the #pywikibot guru; he runs dexbot and it is the only bot with more than 20.000.000 edits. Amir regularly tinkers with the routines that he uses. Sometimes he gets better performance, sometimes he gets a better result.
The algorithm for adding labels has changed several times and, the result of the latest change can be seen in the statistics below. You may notice several spikes, the last one is captured in the last dump; it resulted in many more labels for items where already one label existed.
bot request of his for Commons will help the Commoners see that Wikidata knows about the people mentioned in the Creator templates. Jobs like this are essential when the wikidatification of mediafiles is to succeed.