Former Man United midfielder believes Sir Alex Ferguson's fear of Old Trafford has caused standards to slip.
Ferguson saw the emergence of a talented Frenchman as an adult but refused to bow to pressure from Mino Raiola and allowed him to move to Juventus in 2012.
Pogba returned to Old Trafford four years later with a record-breaking £89 million deal.
Pogba's condition was expected to strengthen again, but the World Cup winner faced questions about his form and commitment during his second time in Manchester.
Giles believes that a stricter approach should be taken with a 27-year-old player, with Klopp is unlikely to tolerate the titles it creates on and off the pitch because he has the German tactic of controlling Ferguson at Anfield.
Giles said: "Manchester United, you could pick 11 players, and on the day, they could be brilliant, and then the next day, not so good.
"Then you also have the Pogba influence. I don't want to keep going on about Pogba, but it's a fact. He's still there, four years after he joined the club, and they're still talking about 'if he does this, will he do that and on his day'. That's not good enough.
"I've said to people, in my opinion, if you said to Klopp that he could have Pogba for nothing, I don't think he'd take him.
"You look at the Liverpool players, and I think they're terrified of Klopp.
"When Ferguson was at Manchester United, players were terrified of him, and that's the way you need it, as they know they won't get away with anything."
Pogba is happy with his late return, but there is speculation about his future after Raiola claimed the Frenchman's time in England.