I agree to this but Pownstar has a point.
As a programmer i realized that the server can randomly generate without actually asking for which pokemon to dig and can just consume an amount of time to generate the digs outcome. If the pokemon with dig doesnt meet dig requirements then it can just say "Your pokemon/s doesnt have enough happiness to dig".
It can be an easy 1 conversation like
But if the Digs result considers the pokemons value/number that will use dig then its a different story.