Value Flow Management Versus Demand Flow Management - Why Does It Matter?
Tuesday, September 25th, 2007In theory of optimization, simplest formulation of the problem consists of a goal (or objective) function, variable parameter(s) within that function for which we want to find optimal values, criteria defining side effects of the goal function being of certain value and constraint(s) that tie parameter(s) to unavoidable limitations. Normally, there are multiple feasible solutions (combinations of parameters’ values satisfying limiting constraints), offering a spectrum of values of the goal function accompanied with a set of values for criteria. Optimal solution is one that defines feasible combination of parameters that gives maximum (or minimum) value of the goal function within an acceptable range of values for criteria. Hence, there is always a trade-off involved between different criteria that come along maximization or minimization of the goal. Obviously, changing constraints and/or relaxing criteria leads to different set of parameters’ values that define optimal solution.
Why this theoretical background? Simply because, it is then obvious that optimal customer solution is very different when we deal with already designed product, and when we deal with multitude of alternatives that have yet to be designed. When optimizing supply chains, our constraints are already put in place during design of the product providing for a limited set of feasible solutions and allowing us to consider simple goal functions with just few criteria (let’s say minimize delivery time with lowest possible cost of transportation and limited inventory). Over-constraining makes optimization simpler, but at the same time, reduces our chances to truly optimize value to customers. In supply chain optimization, value of product to customers is approximated by aggregate forecasts with several pricing scenarios tied to projected volume of demand. We then trade-off between availability of the product to customer, production resources allocation (capacity and materials) and cost of delivery (inventory and logistics). Often, for any given demand and warranted delivery terms, the only two parameters that we can really play with are capacity and inventory.
In product development, we have to maximize utility of products to customers while minimizing cost of materials and production assets required. Demand is then not an aggregate probabilistic volume/pricing curve, but a complex goal function dependent on a spectrum of possible value propositions estimated with much more uncertainty (let’s say a set of innovative features we have never designed before). The problem is very different and consequently our approach to optimization. Nevertheless, certain techniques are interchangeable (e.g. simulating using genetic algorithms within a set of pre-textured feasible solutions).
This would not be much of a problem if each discipline carried well divided responsibilities - design and engineering optimize utility (aesthetics, ergonomics, performance, functionality, quality, direct costs), and supply chain optimizes availability and production assets utilization (capacity and inventory). This was the case when planning horizons between the two areas of responsibility were much apart and of different order of magnitude (e.g. product development cycle was three years, while materials and capacity planning cycle was three months). Today, with accelerated shrinking of development cycles and profitable product life cycles, the situation is much different - with the two horizons not only converging into a single horizon, but planning cycles being virtually of the same order of magnitude. Picture below illustrates the point.

View image
Let’s discuss the picture for a moment. Three immediate conclusions come to mind:
1. Product introduction horizon (the time horizon for which product development resources need to be allocated to the portfolio of new products) is now of same duration as materials and capacity planning horizon (the time horizon for which materials and capacity are allocated to production).
2. Product development cycle (how frequently a new product is released to markets) is the order of magnitude of the materials and capacity master planning cycle (how frequently are key material and capacity constraints aligned with the changes in demand forecast). Thus, it is not uncommon that within a single product development cycle, master resources plan is done only once.
3. The overlap between the two horizons can cover an entire master planning cycle, e.g. production resources plan must be created well before the product design has been finalized, and then often changed immediately after launch.
It follows that demand forecast used for planning product introductions has to be the same one used for planning materials and capacities. Hence, if we know what target markets (competitive acceptance, volumes, prices, options, …) we need to maximize flow of new products to, we have actually determined our demand forecast. It does not make sense to double guess demand once we start planning allocations of materials and capacities, when we have already justified allocating development resources on designing for a specific set of requirements (features, volumes, costs, …) including targeted demand. Things will not change much since the two planning cycles are firmly within same horizon and with overlapping cycle times. Even if changes happened, they would rather be within acceptable tolerance from originally assessed market acceptance of the new product.
This new reality requires a a new planning paradigm - value flow management. Not unlike demand flow management, in value flow management, a common planning horizon is divided into time fences of different granularity within which planning decisions progress from more degrees of freedom (less constraints) to more constrained trade-offs. Unlike demand flow management, value flow management deals with both supply to demand matching, as well as product features to customer value matching. Herein, value is tied to demand. Picture below illustrates this paradigm.

View image
In a summary, value flow management is constrained based planning method used to maximize flow of value to customers, and product margin to the manufacturer by leveraging innovation to limit fluctuations of materials flows and assets utilization.
In value flow management, product development fully integrates with supply chain management to optimize both development and production resources. Single (or synchronized) demand plan is derived from a well targeted value proposition to determine pricing and production volume that will keep materials and capacities within a steady takt with minimal change to both product development and production plans. For as long as there is significant innovation leverage in the product, demand is driven by elastic pricing, keeping supply chain operating within targeted (plus/minus tolerance of the materials flow fluctuation) adaptability. Thus, plans can be optimized early, products developed to match targeted value proposition and then produced within predetermined steady takt that warrants minimum inventory and maximum capacity utilization. When the product life cycle within the targeted product margin and volume production cannot be further extended by reduced pricing, that product has lost its innovation leverage (differentiation to competition) and a due replacement must be timely planned within the portfolio of products.
Value flow management thus eliminates the need for forecasting of demand beyond the final determination of targeted value proposition. In other words, if we are smart enough to allocate development resources based on specific market needs and pricing, why would we start double guessing our business case within the same time horizon for which we have already planned assets. We can decide to stop development though before major costs have been committed, however once past the launch time fence all our capacity and material constraints have to be within tolerance of the profit margin that warrants manufacturing of targeted volume. Forecasting thus gets replaced with intelligent requirements management, whereby requirements need to cover all aspects of business planning and life cycle value proposition from idea to the end of life. Our design decisions need to be postponed until requirements have been fully evaluated, and then fast product integration needs to bring everyone on the same page around the targeted value proposition. The decisions thus get elevated to the portfolio level where multiple scenarios need to be planned for, and changes in plans are made before they have expensive impact on resources in development and production. Development and supply chain have thus been finally merged into a common phase-gate decision model with common planning horizon, total enterprise resource and assets allocations (development and production budgets), and integrated value and demand planning to fully reconcile innovation push with market pull.
Value flow management is applicable to all consumer driven industries - from high-tech, semiconductor, consumer electronics, passenger vehicles, commercial airplanes and consumer packaged goods, where cycles of product development and supply chain planning have converged to market driven takts (e.g. it takes 12 months to develop a yearly vehicle model). The entire planning method centers around two parameters - innovation leverage obtained by creative development and adaptability of the supply chain to match dynamically adjusted pricing with a steady flow of materials (within targeted plus/minus adaptability). Strategies like reuse, virtual manufacturing, simulation based robust design and collaborative portfolio and requirements management play major role in our ability to practice value flow management.
This method firmly positions responsibility for product success to collaborative effort between value creators and value deliverers. The trade-offs associated with this very lean approach to planning (like with any other lean technique) are in favoring our ability to maximize use of knowledge and business intelligence over our ability to react to unpredicted changes in market conditions. I leave it up to discussions if this is better approach for global manufacturers than traditional planning of demand flow decoupled from innovation flow. In the meantime think how and why can Apple justify slashing price of the iPhone by nearly 40%?


