This is purely for aesthetic preference or leaderboard ranking. Players battle specific wild Pokémon or Gym Leaders to bring their experience total to a specific, "clean" number (e.g., 100,000 or 111,111).
You must defeat all Gym Leaders in a region to earn the regional ribbon, which is also necessary for unlocking Legendaries. pokemon vortex level 100 training
Your account's total experience and average experience are key metrics for community rankings. Summary Checklist for Fast Training This is purely for aesthetic preference or leaderboard