Miserable, wretched both describe something (as a person's state of health or of mind, a state of affairs, a human being with reference to his condition or character, or a thing compared with others of its kind) that is deplorably or contemptibly bad or mean.
A person is miserable if in misery or in a state either of extreme or acute distress of body or mind or of pitiable poverty or degradation.
A thing is miserable when it is exceedingly mean or paltry, and provocative only of misery in the person affected or of strong distress or dislike in the observer.
A person is wretched who is extremely unhappy or abjectly despondent (as from want, grief, oppression, affliction, or anxiety); a thing that relates closely to the happiness of a person is wretched if it produces such dejection or mental suffering.
A thing, in general, is wretched if it is extremely or deplorably bad.