Molby told the Daily Star Sunday: "Carroll is never going to be a starter at Liverpool under Brendan Rodgers because he doesn't fit into the philosophy of the manager.
"I am not sure he is the answer, especially with the way Premier League defenders defend these days.
"He is an option to stick on with 20 minutes left of a match. At times, when he is at it and performing at his best, he is unplayable - as he has proved in spells during his loan deal with West Ham.
"But I can fully understand why Brendan doesn't fancy him ahead of Luis Suarez or Daniel Sturridge.
"If they can rake in £17m for Carroll, that sounds like a good bit of business. Then you might well be able to get a Christian Benteke.
"He has surprised a lot of people with his goals but I would like to see if it is more than just his physical power that has given him an advantage over defenders this season."