The 21-year-old Belgium international signed a five-year deal with the Merseyside outfit on Wednesday after swapping Stamford Bridge for Goodison Park in a £28m deal.
And Mourinho has revealed that the forward, who scored 15 goals during a season-long loan with the Toffees last term, said he was not prepared to earn his place as a first-choice striker in west London.
He wanted to play for Chelsea, but he wanted to be first-choice striker
“The thinking behind that was, first of all, the fact that Romelu was always very clear with us in his mentality, and his approach was not highly motivated to come to a competitive situation at Chelsea,” said Mourinho.
“He wanted to play for Chelsea, but he wanted to be first-choice striker, which with a club of our dimension is very difficult to grant a player first-choice status.
“That reduced immediately his desire to come to us. After that Everton come with an important offer and as I always say, as it’s the reality of our club, we want to be inside of the rules of Financial Fair Play, and when we have the chance to make some movements that create a positive impact in FFP, Chelsea always analyse these situations.
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