What is the point of an active shape model in facial recognition? From what I understood, the Active Shape Model (ASM) is used in facial recognition. I figured out how the ASM works but I don't get why we use it.

How this shape is suppose to be interpreted for facial recognition? Should it be compared directly to the database?

I have read many research papers about ASM and facial recognition but none of them explains the point of it.
The active shape model algorithm is used to locate precisely the eyes, eyebrows, nose and mouth of a person. It is also used to align faces that are tilted.
It is not used directly for face matching and it has nothing to do with databases. It is a preprocessing step.
You (I) will need another algorithm to match its result with a database. (ICA for example)