why didn't my Pichu evolve :(

So I was playing Pokemon Moon, as I do, and I was working on raising my Pichu's friendship level

I got him to 5 hearts of affection in the Pokemon Care thing, so I decided to feed him a Rare Candy

And yet, no Pikachu. Anyone know what this is?

Affection Stat =/= Friendship

Then what's the point of it even being there?

^ Affection affects the chances of Pokémon hanging on at 1HP among other effects

Friendship is used to determine the BP of Return and Frustration, as well as the evolutions for certain species

Well that's confusing...

What do you think?