The drug is used to improve the 'quality of life' for patients who have chronic illnesses. [=to make their lives more pleasant and enjoyable]
She has raised/improved her 'quality of life' [=she has become more successful] with her new career.
The restaurant serves food of high 'quality'. [=the food at the restaurant is very good]
(..) in your elbows or your shoulders. Between that and the scar tissue on your kidneys, the residual concussive damage to your brain tissue and the general scarred-over quality of your body, I cannot recommend that you go heli-skiing, Mr. Wayne. Right. We were in this together... (..)2012 The Dark Knight Rises