-- Category:Creates models from scratch - As you read, this is for modelers whose primary work consist of making models with a 3D program. They have ownership over the texture, artwork and pixels placed onto a model.
-- Category:Creates models by editing - As you read, this is for modelers whose primary work consist of making models from other people's models, they commonly use PMD Editor. They may sometimes create original textures but largely the model is considered an edit if the creator states it as such.
And as before the modelers can be sorted into both categories if they have indeed moved from Editing models to creating their own. If a modeler has been editing their own models to make duplicate or new models, then still, that will count as being from scratch as that is their base to begin with.