Sep 16

Mental Models for Product Managers – Part 2

Brain Wiring

Brain Wiring (by Wellcome Images, CC licensed)

In part 1 I introduced mental models and some reasons they are important. And I provided a few “general purpose” examples. In this part we dive into what you really came here for – product management-specific mental models.

Why are product management-related mental models different?

The mental models I’m going to talk about share two key characteristics:

  • They are about about products
  • They are not used enough

We have some great mental models in product management. But we have not been doing a great job of using them to help us make better products. While I think a lot of us have intuitive ideas about “how to think about” product management, my observation is that these mental models are not as widely used as they should be.

I wouldn’t be surprised if you haven’t even heard of these mental models. And if you’ve heard of them, you may not know how to use them.

The value proposition

For example, one of the powerful mental models is “the value proposition.” I’m sure you’ve heard this term. It’s very easy to say, and rolls off the tongue. Yet in my experience many product managers don’t know that a value proposition has a specific structure. A properly constructed value proposition is extremely compelling to prospects. But a “value proposition” that doesn’t have the four specific components of this structure is significantly less powerful.

What are the four components?

  • Who the product is for (the market)
  • What the product is (the category)
  • What the product does (its key features)
  • Why my product is a better choice for you (the differentiators)

This is the classic framework from Geoffrey Moore’s Crossing the Chasm. I’ve written about value propositions at greater length in A Weak Value Proposition Is A Symptom, Not A Disease.

Mental Model Categories

The value proposition is a mental model in the form of a template. It gives you a structure for your thinking and research. I like using good templates. Of course they are used throughout our domain – a user story is a very simple template, a Jira issue is created using a template. And most product management tools are essentially a database of items created by filling in templates.

But there are other types of mental models. While categorization itself is a type of mental model – the idea that different topics or pieces of information fall into different buckets – it’s not a product management-specific concept. But let’s use the categorization mental model to help organize some more product management-specific ideas.

One possible grouping is:

  • Templates
  • Categorization tools
  • Heuristics and algorithms
  • Cognitive laws

I’ll give a few examples of each in this post, and follow up with deeper dives in future posts.


  • The Value Proposition as discussed above
  • The Three Laws of Marketing Physics: For the best chance of success, your product should have 1) an Overt Benefit, 2) a Dramatic Difference, 3) a Real Reason To Believe. For more, check out my article on Doug Hall’s Three Laws of Marketing Physics, or his excellent book Jumpstart Your Business Brain!
  • My V.A.L.U.A.B.L.E. rubric for product requirements. I have a podcast episode and a downloadable graphic about this approach to requirements.

Just because you have a template it doesn’t mean your job is done. Filling in the templates is often extremely difficult. For example, articulating a meaningful Dramatic Difference or “differentiator” portion of the value proposition is usually difficult. (This is especially true if your product is really “a solution looking for a problem.”)

Categorization tools

Categorization is not a product-specific concept, but there are some categorization tools that are specifically about product. Here are a few of my favorites:

  • Stack ranking. It rests on another critical mental model, which also underlies “agile” – this is the idea that focusing on the most important thing first is the best use of your time.

Stacking ranking is a “one-dimensional” structure. The next set of examples live in two dimensions:

2x2 Mental Models

Cost vs Value Matrix2x2-of-requirement-cost-vs-strategic-scoreThis chart allows you to plot features or projects based on their cost (x-axis, lower values to the right) and their market or strategic value (y-axis, higher values to the top).

The upper-right quadrant of this matrix is features or projects that are inexpensive relative to the value they will deliver.

Features or projects in the lower left quadrant are expensive relative to the value they deliver.

You can make this chart more expressive using bubble size and bubble color (for example, perhaps the color of the bubble represents the risk of the feature or project).
Magic Quadrantgartner-magic-quadrant-software-test-automation-2016-2015_0This is the famous matrix that Gartner uses to categorize vendor products. The y-axis represents "ability to deliver," while the x-axis represents "completeness of vision." The upper right "magic quadrant" is vendors who have a compelling vision and can deliver on it.
The "Eisenhower Matrix"eisenhower-boxMade famous in the book Seven Habits of Highly Effective People, the Eisenhower matrix directs us to strive to spend our time on activities in the Important and Urgent quadrant, and to assess where we actually spend our time (often in the not-Important, not-Urgent quadrant, unfortunately!)
Trikro's Lean Startup Test Categorizationthe-lean-startup-playbook-1024x818Tristan Kromer has laid out a nice categorization of lean startup experiments based on whether you are looking for an idea or testing an idea you already have, versus looking for a market for the idea or validating that your solution to the idea meets the market's needs.
The BCS Growth-Share Matrixbcg-matrixIf you have an MBA you know this matrix. It's useful for evaluating the balance of your product portfolio. The y-axis represents market growth, the x-axis is market share. Each quadrant has a name, such as the "Cash Cow" - products with large market share in markets with slow growth. Cash cows throw off cash (hence the name) that can be used to grow Stars - products with a small share in a high growth markets. Dogs, of course, are products with low share in low growth markets. Usually you want to get rid of your dogs.

Categorization tools are helpful for making decisions and prioritizing features or portfolios.

Heuristics and algorithms

Technically, heuristics and algorithms give you steps to follow in specific situations. But often the steps involve reconceptualizing the situations, which puts them squarely in the province of mental model.

For example, there are some great heuristics in Chip and Dan Heath’s book Decisive that can help us make better decisions. The book is a great and entertaining read. And Teresa Torres has written a number of great articles putting a product management spin on them.

I’m going to touch on two of their mental models about decision making:

  • It’s never an either/or decision – you can always find more options than Yes/No, Go/NoGo
  • The 10/10/10 rule – think about how you’re going to feel about this decision in 10 days, in ten months, and in ten years. This rule helps you get out of the rut of taking hasty action now that you might regret later. Getting caught up in the urgency of something that might not actually be important in the long run. I illustrated the use of this rule in my article 5 tips for when your release is running late? You can push to get it out on time, even if there might be quality problems. That’s going to make you and your execs happy for a few days or weeks, but it’s going to haunt you next year when your customers stop renewing because of “your history of low quality releases.” On the other hand, if you delay the release until the quality is better – that’s a big downer today and for a few weeks, but in six months no one will remember, and in six years your company will be twice as big because all your customers renewed, citing “very high quality releases every time.”

“Rules of thumb” are another set of good heuristics that represent useful mental models. in my Rules of Thumb series I wrote about a few I use.

Cognitive laws

These mental models are rooted in the way people really think and make decisions (as opposed to how they think they do).

  • Customers don’t know what they want – this is an agglomeration of the results of a lot of different cognitive biases our customers have. Steve Jobs had a great quote, “A lot of times people don’t know what they want until you show it to them.” This doesn’t mean you shouldn’t talk to your customers. But you need to talk to them about their problems, not about “what they want.”
  • Personal goals – this is another one that’s easy to say, and powerful, but hard to do in reality. It turns out that customers and users don’t care that much about the business benefits that our products provide. What they actually care about is achieving personal goals. I wrote about this idea in greater detail in The Best Way To Engage Your Audience Is To Help Them Kick Ass.


I’ve only begun to touch on mental models for product managers – most of these I’ve described with a few sentences.

I haven’t even talked about some of the valuable larger frameworks of mental models (although I do have blog posts about some – like Kathy Sierra’s “badass” approach).

And I haven’t mentioned anti-models – mental models that are actively dangerous for product managers (despite their ubiquity).

So, there will be more coming in future blog posts. But, in the meantime, I want to make sure you have some actionable, concrete advice for making use of these ideas.

Three things you can do today

You can start putting these mental models to use, and work on your own library of mental models, with these three actions:

  1. If you don’t have a value proposition articulated using the four part framework – category, customer, benefits, differentiators – then do it. You’ll learn a lot. This is hard, by the way. And you might find yourself struggling. That’s a good sign. If you’re struggling, imagine how your market is struggling to understand why they should buy your thing.
  2. If you can’t do the 10x thing for your product, get to work on that. It’s also a hard thing. Luckily, in most cases you can do the 10x against business as usual, and not against your competitors. Although if you can do it against your competitors, that’s amazingly powerful. “Not only will you have 1/10 the downtime, but you’ll implement 10x faster than with our competitors.”
  3. Study up on mental models. This really means studying up on ideas – ideas from different domains that focus on understanding how things work, and how things can be improved. A good list of mental models to start from is Mental Models I Find Repeatedly Useful by Gabriel Weinberg.

Sep 16

Mental Models for Product Managers – Part 1

The importance of mental models

Knitted Brain Hat

Model of the brain – in yarn (CC 2.0 by Linden Tea)

There’s been an explosion – at least in my feed – of folks talking about the importance of having a lot of good mental models to help you make better decisions.

A lot of this goes back to a talk by Charlie Munger at USC Business School in 1994. He’s the other old white guy who works with Warren Buffet at Berkshire Hathaway making lots of high-payoff investments. Munger said their “latticework of mental models” is one of their core competitive advantages.

What is a mental model?

“Any concept that helps explain, analyze, or navigate the world.”

I’d also add, specifically

  • That helps you make better decisions
  • That guides you on how to take better actions

Mental models are like tools in a toolbox. If you have only a few tools, you can only solve a few kinds of problems. Like the famous saying – If you only have a hammer, then you have to treat every problem as a nail. If you have a full toolbox you have a lot more flexibility and subtlety about how you can go after problems. And tools that aren’t quite up to the job is almost as bad as not having the right tools. You can’t fix a sink if you don’t have some plumbing tools.

Mental models can also help compensate for your own limitations. We all have limitations in the way we think which mental models can help address. They can be like a mental checklist, or like a jig or fixture. Things we know we should do but forget, or things we normally don’t think about but know we should.

Mental models comprise different types of things: heuristics, “cognitive laws,” templates, categorizations and categorization strategies. And there are hundreds if not thousands of mental models. Munger says “80 or 90 important models will carry about 90% of the freight in making you a worldly‑wise person.”

Mental Model Examples

Some general purpose mental models are very useful for product managers. This short list is taken from a fantastic list of mental models by Gabriel Weinberg:

  • Cognitive bias – and all the particular cognitive biases that arise in different situations.  “Tendencies to think in certain ways that can lead to systematic deviations from a standard of rationality or good judgments.” (See list of cognitive biases.)
  • Ask Why Five Times – Arguing from First Principles .  “A first principle is a basic, foundational, self-evident proposition or assumption that cannot be deduced from any other proposition or assumption.”
  • Scientific Method .  “Systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.”
  • Order of Magnitude.  “An order-of-magnitude estimate of a variable whose precise value is unknown is an estimate rounded to the nearest power of ten.”

You’re probably familiar with these and many more like them already.

Mental models for product managers

What about mental models for Product Managers specifically? There are quite a few mental models about products and making them successful. Too many to cover in this post, which is already getting long, so stay tuned for the next post.

What mental models do you use and depend on for getting your job done?