Page "Perspective distortion (photography)" Paragraph 10
When photographs are viewed at the ordinary viewing distance, the angle of view at which the image is captured accounts completely for the appearance of perspective distortion.
Perspective distortion is particularly noticeable in portraits taken with wide-angle lenses at short camera-to-subject distances.
They generally give an unpleasant impression, making the nose appear too large with respect to the rest of the face, and distorting the facial expression.
Framing the same subject identically while using a moderate telephoto or long focus lens ( with a narrow angle of view ) flattens the image to a more flattering perspective.
It is for this reason that, for a 35 mm camera, lenses with focal lengths from about 85 through 135 mm are generally considered to be good portrait lenses.
Conversely, using lenses with much longer focal lengths for portraits results in more extreme flattening of facial features, which also may be objectionable to the viewer.