No idea, really.
In fairness, Lamela has had a really good season thus far and deserves the start. But it always feels like after Lucas scores, the next week he's dropped to the bench. Or if he does start all it takes is one bad performance and he's in the cold for a little while. Whereas other players are pretty much guaranteed places (thank god that doesn't apply to eriksen now) even though they might stink the place out for weeks.
Always feels like he's never really given a great chance to build up a head of a steam. Although he is by nature an inconsistent player, and again to be fair to Poch he struggles to play alongside Son. It's a bit of a tricky situation though because he's a fantastic squad option but you feel like he's a tad too good for that role.
Sorry, boring case of Poch has his favourites I'm afraid.