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The Tetris Effect

We tend to assume things happen as a result of proximate causes. The plane crashed because it flew into the mountain. If we’re smart, we’ll take into account the ultimate cause. The plane crashed because instruments were broken and the pilot was drunk.

Often the case is even more dynamic. Events which occur in random sequence stack together like tetris blocks, collapsing at key moments, observable only to someone who can see the entire board.


One area where I’m certain this happens is food. We tend to over-fit on the last piece of data we ate, like a broken AI model.

“I don’t feel great. I just had bread, I bet bread is bad for me”. Is it? Or is it the confluence of bread and the 900 other things you did what catalyzed that feeling? What was your previous meal? Did you put butter or olive oil on your bread? How much light did you get today? And salt?

Human metabolism is chaotic. Just like a double pendulum, things get very confusing after the initial conditions are set. Feeling great, bloated, or icky is a culmination of various events that might be hard to retroactively trace. Since we can’t see the entire board we pick one point at random, often incorrectly.


I’ve run about 2,000 times over the past 7 years. I can recall a few of those 14,000 hours extremely vividly. I remember running around an airport in London during a layover almost minute-by-minute. I doubt there’s a singular reason I could point to. It’s likely the culmination of various elements: it was a relatively short run, in cold weather, a novel setting, and I was with great friends. With these factors in mind, I’ve tried to “engineer” memorable runs in the past to little success. What yields a long-lasting imprint on the mind seems to be a culmination of various things. The tumblers in the lock rarely align, leaving even the most technical of locksmiths mystified.

We have just over 6,000 hours of waking hours in the year. Thousands of opportunities to create memories. How many of the past 6,000 hours do you remember? A few minutes? An hour? Wouldn’t it be great to increase that number tenfold?


While it’s fun to pontificate about food and memories, there’s real value in thinking in tetris when it comes to sales. Some products work with direct advertising. People are already searching for lawyers and accountants. All you need is a lead.

Other products are a “discovered need”, often called a considered purchase. It’s quite likely that what you’re building is in this category. The technical literature on how to engineer this romantic journey for your customers is lacking (possibly because the best secrets are kept in house). Like metabolism, the actual buying decision is somewhat chaotic. The tetris moment is hard to predict. The best you can do is provide your customers bountiful amounts of “healthy food”. Be in their face as much as you can by giving them the content they want.

A great example of content marketing is Zapier. One of their most popular posts is “10 Best Calendar Apps for 2020”. The post isn’t about Zapier. The post is about something you’re likely to Google for if you’re a future Zapier customer. Since you can’t predict when the lock will click for your users, your content marketing game shouldn’t be about you. It should be about other things I’m likely to want, so that your company is top-of-mind when the mood strikes.

Life Decisions

Changing jobs. Marrying. Moving to a new city. These large life decisions are the most under-studied, under-rated, and under-thought thing in the universe. The most considered “considered purchase”, in a sense. Unfortunately, I can’t find the manual for how to dissect the process of making large life decisions. (If you have it, please let me know.)

Any assumption that the process is rational should be immediately discarded. It is biome over brains, with the mind providing the post-hoc rationalization as a form of psychological safety. You might ask someone why they’re changing jobs. They might say something like: “I’m not learning enough” (What does that even mean?) or “I don’t like doing X” (What caused you to decide this now?) are often what comes up. These are never the real reason.

Like the processes I’m describing above, the real reasons might have been set in motion months ago, when a friend casually commented on their salary (“Whoa… that’s more than I make! What does that say about me?”), or when they asked you “how your day was” on a particularly bad day (“Note to self: all days are bad!”), or something else. The final block that caused the collapse may have been returning from vacation, which is always the moment where you “retrain” your life models.

“What should I do about this?”

It’s hard, often impossible, to predict the exact block that will cause the wave function collapse. The events aren’t sequential, and you often don’t know the entire board. In situations like sales and recruiting, your best bet is to work to increase the odds that you’re going to drop the right block[1] by showering your customers with goodness they’re interested in.

Concretely: optimize the environment. Spend a lot of time with people you’d like to hire. Send them content they’d enjoy. Do the same with your users. Do the same with your food. Etc. Less time optimizing a specific thing, more time improving the environment around that thing.

[1] Or make the right observation, if you prefer metaphors from quantum mechanics.