In Trainer Battles (Arena, Rocket fights, etc), you can "charge" a move by swiping all of the icons that appear. Depending on how many you hit, you can get a caption showing how well you did; "Nice", "Great", or "Excellent", much like when you catch Pokémon.
When catching a Pokémon, this affects the "strength" of your catch. E.g a "Great" throw is better than a "Nice" throw, which will increase the likelihood of catching the Pokémon. However, I haven't seen much difference for the Charged Moves in Trainer Battles.
So, in Trainer Battles, when executing a Charged Move, is there any difference between "Nice", "Great", and "Excellent", and if so, what effect does it have exactly?