Either would be effective but seeing the belt landing across her bottom would make you realise how effective it was, Seeing her expression might depend on how well you knew her tolerance for punishment.
Waiting for the cane at school was always frightening. But seeing the person before you getting caned was the worst. Watching the cane come down was bad but seeing the reaction as it landed made it worse. So both are bad but I feel seeing the persons reaction is slightly worse.
Either would be effective but seeing the belt landing across her bottom would make you realise how effective it was, Seeing her expression might depend on how well you knew her tolerance for punishment.
So, both then…:/
Waiting for the cane at school was always frightening. But seeing the person before you getting caned was the worst. Watching the cane come down was bad but seeing the reaction as it landed made it worse. So both are bad but I feel seeing the persons reaction is slightly worse.