Given the following advancement, placed in world/data/advancements/custom/horse.json:

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:tame_animal"
        }
    },
    "rewards": {
        "commands": [
            "/say Tick",
            "/advancement revoke @s only custom:horse"
        ]
    }
}

Taming a horse can cause the advancement to trigger sporadically multiple times, though sometimes only triggers once.

It appears neither game mode nor Temper value matter, therefor it is faster trying to reproduce this with Temper:100 horses:

/summon horse ~ ~ ~ {Temper:100}