This Is The Cup That Never Ends... | Summer Cup GBL | Pokémon GO Battle League 

Depending on when you use your charge moves, opposing Pokemon may get to use additional fast move. So, for example of I use my charge move on the same turn you use your fast move, you'll get that entire move during the charge move sequence. It becomes very important when facing things with moves like Incinetate to avoid giving them an entire move (and the damage/energy that comes with it) just because you mistimed your move.