I've played all the mainline games up until Sun/Moon,
but I only ever beat Pokémon Blue (beat Blue multiple times with each starter).

With Gold, I stopped playing when I got to the Dragon's Den.
With Ruby, I stopped playing when I got to Lilycove City.
With Diamond, I stopped playing when I got to Eterna City.
With White, I stopped playing when I got to the Dreamyard.
With Sun, I stopped playing when I got to the Trainers' School.

What about you?