It seems generally accepted that players tend to push (and extend) their limits with competition for their position, so surely putting these clauses in loan deals makes them a pointless, and possibly counter-productive, exercise for the parent teams.
Either Grujic plays well, confirming that he's a good player, but is never required to really stretch himself because he's guaranteed 1st team football anyway. Or, he struggles, is resented by the fans (and possibly his team-mates), and returns to Liverpool damaged.
Perhaps I'm being biased, but I imagine that the CCV scenario - in which he was dropped for a couple of dodgy performances but fought his way back into contention - would be far better for a young player's development. After all, top level youth players are already supremely talented. The whole point of a loan is to develop their mentality.