Do some fillers simply not work for some people?
Not really. All fillers should work for all people but there are certain people that filler will only last 2 months for while another person may retain the same filler for 2 years. Therefore there are averages as far as longevity of fillers. Now not everyone is a candidate for fillers depending on medical condition; and certainly some fillers are better for some areas of the face and other fillers should totally be avoided in some areas of the face.