Behavioral Design Models

1. Product & life

The most important question to answer is what behaviors to design for. Products are living things, so let's use life's processes to discover the behaviors that make your product a viable and self-sustained system.
The most important question to answer is what behaviors to design for. Products are living things, so let's use life's processes to discover the behaviors that make your product a viable and self-sustained system.
  1. Make three columns labeled Growth, Nurture, and Reproduction
  2. In the middle (Nurture), list the behaviors that get users some value regularly
  3. Under the Growth list, all the behaviors required to be in a position to do the nurture behaviors
  4. Under Reproduction, list all behaviors that can make another user begin using the product

In research, the researcher selects a behavior that is interested in driving and works from that point onwards. In Business, knowing what behavior to nurture in your users is not as straightforward. Selecting which behaviors your product will attempt to provoke in the users, in what priority, and the effort to devote to create them is what makes a product live or fail. Yet, most times, we don't think in terms of behaviors but in features. This methodology will help you craft a product from a Behavioral Perspective.

I've worked with several entrepreneurs who lost sleep thinking of adoption and churn rates, adding features, tweaking things around, but never considered a simple question. What do I need the user to do to realize that my product is worth their effort? (I mean effort as a general concept, could be money, time, attention, etc.). As I see it, there is one law to follow when designing a product:

Users must get more value out of the product than the effort they put in.

Sounds simple, but it is easy to lose track of this fact. This set of articles contains a series of exercises to keep you focused on this fact while developing the list of features your Minimum Viable Product (MVP) should have. It's not wrong to lose sleep over adoption and churn (or retention) rates, but it will be of no help if you are not aware of the real value you are providing.

The First Template

A good product is an ever-evolving complex system that learns from each user. In this sense, a product is very much like a biological species, each successful instance affecting the experience of the next ones. Adoption and Churn rates are like born and mortality rates; when the mortality rate overpasses born rate, extinction happens. But that's not all; just like life, a product needs to grow, nurture and reproduce.


Users use things because using them is less troublesome than the benefits its usage provides. For example, loading the dishwasher might be a pain in the back, but it certainly beats having to hand wash every item. Moreover, each time the user performs this action, it nurtures his conviction that a product provides a good deal. This keeps the user engaged with a product. However, to be able to nurture effectively, a product must first grow on a user.


Living things are not born mature beings; they require a series of transformations to effectively nurture. Mammals are not even capable of process the food they will eventually consume from the get-go. This is true for a commercial product; the product's birth is just a desire of the user to know more. That desire alone will not be enough for the user to comprehend, let alone get any value, from the product. The product needs to provide ways to grow on the user. To allow them to explore and decide to invest the effort to first obtain the value. So, growth includes tutorials, sign up, even marketing material; it's the adoption process.

The adoption process (Growth) should cover everything needed for the user to get value out of the product effectively.


A product needs a never ending influx of users. Even the most loyal user will, eventually, churn. Users will stop paying a subscription service, decide to buy a new car from a different company, or maybe they'll die. Nature solves this by spawning individuals from individuals; unfortunately, the best we can do in product design is mouth-to-mouth. But you can have a team of sales or social network ads too. The point is that the product often needs somebody (other than the user to be) to do something to get you more users. These are the reproduction behaviors.

Reproduction behaviors often rely on the surplus of benefits that the nurturing behavior has accumulated. This could be money spent in campaigns from active subscriptions. Or, it could be that the product is so good a user decides to share it with his friends.

The model

My first model is a simple one, three columns (growth, nurture and reproduce) to list what behaviors are involved in each of these categories. It serves to center the design in the essential: the behaviors we need to design features for. The following models use this list as an input to expand on the minimum viable product scoping.

Write each behavior using a short title. As a prefix, I use a capital B (denoting behavior) and a capital G, N, or R to indicate its intent. For example, take the usual sign-in behavior: "Get the user to provide a way to identify him securely." It will be referred in all my documentation as "BG-Sign Up." This reminds all the team that we are not designing a form; we are trying to get the user to fill it as a part of getting to know the product.

Model 1 - Empty

If your lists are complete (we will revisit that in models Model #2 -Actors Requirements and Model #3 -Type of needs ), you can design features that lead users to perform that behavior(models Model #3 -Type of needs and Model #6 -Target Behavior Funnel +) and prioritize everything in the right way (model Model #5 -Design Effort ) you have no way to fail.

Model 1 - Example

I reckon those are a lot of ifs. Still, with the help of these design models, the product's design will be directed on what really matters; user behavior.