Costa's movement can be sublime at times (like the first half of last season) but he is wasteful not just with chances but his general lack of ability constantly killing any hopes of building play.
Honestly, I've just had enough of pretty much all of our players. A couple of months ago I had Costa down as one of 5-6 players I'd keep no matter what but now I genuinely couldn't care less. Why place faith in somebody who you're unsure is going to be able to control the ball?