The 22-year-old came on for Juan Mata at half-time in United's 4-1 Carabao Cup win over Burton Albion nearly five months after he suffered a foot injury in the Premier League win over Swansea.
"When I see someone that's been criticised by his manager publicly and he's probably fighting for his Man United future, come on in a game like this against Burton, you're 3-0 up, there's nothing to lose and you've just come back from a long injury, you absolutely sprint everywhere," Neville said on Sky Sports.
"And I didn't see that real hunger to sprint to every ball, to sprint forward, to sprint back, I saw someone that's coasting. He needs to come out of that comfort zone of coasting because if he wants to be a Man United left-back he needs to play at the level of a Ander Herrera.
"He [Herrera] got his chance tonight and he flew into every tackle and went into every ball and Shaw needs to get up to his intensity every minute of every game he plays for this football club. At the moment he's not. He looked a long way off.
"I know he's been out injured but we're waiting for the real Luke Shaw. I think he's good enough to play here but I need to see more from him."