For a story I’m working on, I came up with the following concept about magic:
There are two kinds of spells – generic and fingerprinted. Only the one who cast the spell can remove a fingerprinted spell.
There are only two reasons to cast a fingerprinted spell – you are the first person to do this kind of spell and it hasn’t become generic yet, or you want to make sure the spell sticks.
It takes a lot of energy to fingerprint a generic spell, so it isn’t done often or lightly.
The loop hole – if the originator dies without releasing the spell – but it is difficult and costly and the person who is enchanted may die in the process.