S6 camera focus issues?

[MonkeyNews]

I'm not sure exactly what the problem here is or even if there is one but the focusing on my phone seems sporadic. If I bring up the camera, sometimes it will focus well on an image, but other times it will just refuse to focus on certain things no matter how many times I tap on the area I wish to focus on.. Am I just being stupid and missing something? Or have people had issues with the camera? When it works, it works amazingly. But it's rather annoying that it won't focus on things all the time.