It may have to do with the laws of nature that two entities interconvert or call for one another as is the case with my face and act. Knowledge calls for hope, warmth calls for trust, freedom calls for courage, beauty calls for relief and so on.
In the world of people, the perception of “face” is a great matter of subjectivity and variations and, therefore, should rely wholly on the “act” to which it is linked. This assumption may make many people comfortable as for however and whatever they look like in terms of physical characteristics because they can have a reasonable approval and palatability merely through doing fair and good.
It may be thus everyone’s concern as for the type of “act” that is automatically called for by his/her “face”.