Advantage of dynamic models

What are the advantages of a dynamic model compared a static model?

Yes, I understand that these features include.
> A dynamic language model that can be changed at runtime.

In terms of speed of decoding, I think the static model is superior.

The following script looks like generating a dynamic model, why a dynamic model. Does it have any advantage?
https://alphacephei.com/vosk/models/vosk-model-en-us-0.22-compile.zip