Teenage star Sterling is expected to seal a fresh five-year deal before the weekend as the Anfield club bid to ensure they do not lose him to rivals Arsenal or Manchester United.
But Liverpool boss Rodgers does not want to see the England international then think a lucrative contract means he no longer has to work hard.
Ahead of Saturday's Premier League game against Fulham, Rodgers said: "I always congratulate players when they sign a new contract and then I warn them.
"I tell them they need to decide after this contract whether there is going to be another at one of the biggest clubs in the world or whether it will be at a different level.
"They can't rely on this contract and I make sure they know that. They have got that contract for what they have done in the past."
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