It's not supposed to.
Don't store data in the chain.
OP_RETURN is like saying "please don't rape me! but if you do, please be gentle".
It doesn't justify or make the rape (abuse of the blockchain, in this case) easier.
Or another way I've seen it phrased, "I can't stop you from raping me, but please be gentle."
To clarify, the only reason that OP_RETURN is in marginally better than other methods of inserting arbitrary data into transactions is that it doesn't bloat the UTXO set, because it can be pruned from there.