I think he's been a late bloomer to be fair. Everton signed him for his potential and he's obviously worked hard on his game as he's developing all the time. I'd say that the kind of striker he is, bar the odd anomaly they tend to start getting recognition as they get older, and that's when the goals start going in.
No doubt he is practicing finishing in training, but I reckon a lot of the work he's put in at Everton, has been on the other areas of his game, holding the ball up and trying to bring others in to play. That's the part of his game which has improved the most. DCL will have been told to hold the ball up and try and bring the wide players in to play, and then get in the box. Basically in the pro game it's all about not giving the ball away, and therefore allowing the team to create the shape and patterns they will have worked on. Lesser players give the ball away often and it's those transitions which kill the team.
We saw a little of it on Sunday to be fair. The ball was played up to Kean and more often than not it just came straight back, unless it was hit in to the space that bournemouth left in behind. That's probably why he hasn't started more, because as a team Everton have struggled with the transitions for years, and we are always vulnerable to the counter, cos the side has no mobility.
15 goals is still a decent return in a struggling side to be fair, and as I said earlier, he's the kind of striker who will keep improving on his game and get better. Whether he ends up being good enough, we don't know just yet, but there's a player there and I think he gets a lot of stick for things others players get a pass for.