> But material design is not a complete school of thought.
Yes, it is. Its actually more of a "complete school of thought" than, e.g., "flat design", which is a vague, ill-defined, poorly-bounded element of an approach to visual design, not a complete school of thought on UI design.
> Other companies are going to want their own design language, to distinguish themselves from their competitors.
Some may, some may not. Design language is hardly the only potential axis of product or company differentiation. Furthermore, you can differentiate on design within the parameters of a design language like Material Design, because -- while fairly comprehensive -- it doesn't dictate all aspects of design. Defining consistency in the areas Material Design leaves open produces a distinct design that is still completely within the bounds of the Material Design.
You're confusing complete with specific. The material design language offers specific solutions to specific cases. But what designers need more is a general theory they can apply to any situation. And the theory behind material design doesn't fundamentally differ from flat design, other than it's focus on animations. It still shares the principles espoused by flat design people (authentically digital interfaces, minimalism).
No, I'm not, I'm saying design languages with well-defined motivating principles like Material Design and Microsoft's ex-Metro language are both more complete schools of thought on design (starting with identified principles that cover broader scope of design problems) and more specific, well-defined approaches to design/interaction (clearly defining both foundational principles and the applications of those to specific areas of design) than things like "flat" design.
Yes, it is. Its actually more of a "complete school of thought" than, e.g., "flat design", which is a vague, ill-defined, poorly-bounded element of an approach to visual design, not a complete school of thought on UI design.
> Other companies are going to want their own design language, to distinguish themselves from their competitors.
Some may, some may not. Design language is hardly the only potential axis of product or company differentiation. Furthermore, you can differentiate on design within the parameters of a design language like Material Design, because -- while fairly comprehensive -- it doesn't dictate all aspects of design. Defining consistency in the areas Material Design leaves open produces a distinct design that is still completely within the bounds of the Material Design.