I have a tendency to shoot at very wide apertures (in the vicinity of 1.8 often). It creates nice soft backgrounds but the cost can be sharpness of the subject. When taking pictures of people, I find that most of the time, we will put up with blur as long as the eyes are sharp. So, when shooting, I make sure to focus there and then re-frame before firing away.
Here, you can see Kie’s left eye is sharp…and the right is mostly sharp (I should have been stopped down a touch). The middle would have led to a sharp nose and blurred eyes…which would not have been usable.