The Belgium international, who was also linked with a return to Chelsea, feels it was “too early” to move to Italy but admits this could be his last season at Goodison Park
Lukaku, who scored 25 goals in all competitions for the Toffees last season, was strongly linked with a move away from Goodison Park this summer.
Chelsea were reportedly interested in re-signing the Belgium international, who they sold to Everton in 2014, while Juve were also touted as a potential destination.
Despite missing out on continental football by staying at Everton, Lukaku, 23, felt it was the right decision to stay because it was “too early” for him to move to Serie A.
"It stings a little [not being in European competition], but I'm someone who believes that everything happens for a reason," Lukaku said in an interview with Het Nieuwsblad.
"Otherwise I would have gone to Juventus instead of staying at Everton. But I opted for Everton because it was too early for Italy and I have not done badly here.”
Lukaku has also revealed he did not have too much of a choice due to Everton's reluctance to sell him, but admits this could be his last season at the club.
He added: "Now we have a new coach and it is completely different than with Mr [Roberto] Martinez, but I think we can make progress under Ronald Koeman. It may be the last step and then look further.
"I knew of the interest of a few clubs, it was quickly very clear that Everton would not let me go. It was important to me that I remained calm, and I did.
"I said to myself that I will do my best and who knows what will happen in the future."
Everton are believed to be interested in offering Lukaku, who has three seasons remaining on his existing deal, a new contract.
The striker says he will decide whatever is in his best interests but insists he will continue to work hard for his club regardless.
"I tell [agent] Mino [Raiola] what I think about it [contract renewal] and eventually we have to make the decision that is best for me," Lukaku said.
"For me football is not about money – I want to win prizes. But when I get into a situation where I can leave but my team will not let me, I'm not someone who misses training, gets fined and develops a bad reputation.
"I try to remain calm and treat my club with respect. Hopefully they also treat me with respect and I can leave through the front door."