Why using raw type causes the properties to become raw?

Question

I have a generic class, defined as follows:

public abstract class BaseModel<T extends BaseModel> extends BaseEntity<T> {
    ...
    public Map<String,List<BaseModelConcrete>> itemsToDelete = new HashMap<>();
    ...
}

every time I get a BaseModel argument to a function, the property becomes Map, but when I change the argument to BaseModel<?> the argument is Map<String,List<BaseModelConcrete>> again.

Why is that ?