Romelu Lukaku had it all. Or, more accurately, all that you can reasonably expect to have when you're a 30-year old forward who under-performed relative to his massive salary, suffered through an injury-hampered campaign, missed sitters on the biggest stage (like at the World Cup and in the Champions League final) and is under contract with a club like Chelsea, who don't want him and are desperate for him to leave.
Lukaku had a team and a city who loved him -- a place where he was comfortable, having spent three of the past four seasons there.