I think his biggest problem is his shooting ability. For a striker, he has nowhere near enough quality attempts at goal. I believe this is down to an alarmingly limited variety in ‘types’ of shots he can take. Take Martial’s second goal against Chelsea, or Kane’s finish against Barcelona. These are regular shots for any decent striker, no ‘goal of the season’ contenders. But I can’t see Lukaku performing this kind of bend into the bottom corner. You look at Martial’s goal against Burnley last season, or Rashford’s bend against Liverpool last term. Another that Lukaku could never.
Typically, Lukaku will score a header or from a range where the power is more important than the accuracy. The types of finishes that require greater emphasis on finesse or accuracy, he doesn’t have. He’s a powerful guy, but doesn’t have the shooting technique for a really powerful shot from 15-25 yards, not without losing accuracy. Not the finesse to bend. It’s been a while since I played computer games, but on Pro Evolution, there used to be a player stat called ‘shot technique’ years ago. This is underrated and perhaps just taken for granted amongst top forwards. Players like Lukaku, or Valencia are not capable of a simple bent finish.
He has far too few shots on target for our leading striker. This is not down to ‘service’. ‘Service’ to Lukaku is limited as there is only a certain type of situation he can fashion a shooting chance out of with any consistent basis. There is no silk at all to his game. None. As a forward player, you need that, otherwise you’re not a million miles away from when a team sends the Big centre half up front to chase a goal. This is why many opportunities that seem presentable end in scuffed shots for Lukaku. He has very poor shooting technique.