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The “Not Invented Here” syndrome

An idea, a component or a method is set aside not for its flaws, but because it does not come from us.

Bias≈ 10 min readPartly checkedPartial checkThe main facts were checked by searching the cited sources. The items below still need checking before relying on them.To re-check
  • Chiffres Procter & Gamble (4,8 % → 3,4 %, ≈ 60 %, 10 % → 50 %) tirés de résumés web de Huston et Sakkab 2006 ; l'article cite plutôt 35 % pour certaines mesures
  • DOI de Katz et Allen 1982 à contrôler
Written with AI assistance; sources are cited at the bottom of the page. An error? Report it via clement13.net.
Reading
FrequencyFrequentSeveral times per project.
Where you meet it
  • Component choices
  • Reuse
  • Open source
  • Tool choices
  • Relations between teams
  • Innovation
AI helpPartialIt helps, but it falls into the trap too. See how ↓
In brief
  • What: we dismiss, or rebuild in-house, what was designed elsewhere, without having evaluated it on its merits.
  • Why: professional pride, group identity, perceived loss of control, fondness for what we built.
  • Detect: “we'd do it better ourselves,” different evaluation criteria for outside and inside.
  • Avoid: compare build, buy and reuse on the same criteria, cost the full picture, keep a decision log.
On this page

Definition#

Avatar of Ralph KatzFictitious illustration
Ralph KatzAmericandate of birth not publishedInnovation management researcher, co-author with Thomas Allen of the 1982 study on the NIH syndrome

The “not invented here” syndrome (NIH) is the tendency of a group to reject an idea, a product or a practice because it comes from outside, even when it would fit. The typical result: we rebuild in-house what already existed, at greater cost and often with lower quality.

The expression is old in research and development management. It was studied by Ralph Katz and Thomas Allen (1982), who examined 50 R&D project groups in three organizations: teams with a long average tenure communicated less with the outside of their organization and performed worse.

It is not a “pure” cognitive bias: it combines several mechanisms (see below) and an organizational factor, the group's culture. That is why it is classed among collective decision biases.

The mechanism#

  • Identity and pride. For a team of engineers, adopting someone else's solution may feel like admitting they could not have built it. Skills and autonomy are part of the group's identity.
  • The “home” effect. We know the flaws of what we wrote and forgive them; we only see the flaws of what we did not write (see the IKEA effect and in-group bias).
  • Perceived control. Depending on an outside component is experienced as a loss of control (lead times, evolution, support). The risk is real, but it is generally overestimated compared with the more diffuse risk of what we maintain ourselves.
  • Invisible costs. The purchase cost is displayed; the cost of building, maintenance and opportunity is not. The comparison is skewed before it has even begun.
  • Gradual isolation. The more stable and closed a group is, the fewer new ideas it receives, and the more suspect it finds them: this is the dynamic identified by Katz and Allen.
An outsidesolutionis proposedCriteria stricterthan for theinternal solutionRejection“we'd do better”In-house development:hidden cost andmaintenanceLess contactwith the outsideRemediessame criteria inside/outsidefull cost over 3 to 5 yearsdecision recordedregular external watchbefore
Each rejection reduces contact with the outside, which strengthens the impression that the outside has nothing to offer. The remedy is to impose an objective comparison before the decision.Hover over or tap an element to read its details.

Where we encounter it#

In project management#

  • Component choices: “we'll write our own workflow engine / data access library / scheduler” when mature ones exist.
  • Open source and vendors: the existing library is dismissed over a minor defect, or a style detail, while we tolerate far worse in in-house code.
  • Another team's tools: the neighboring department offers its testing framework or authentication module, and each team ends up maintaining its own.
  • Reusing what exists: a component inherited from another project is redone “because we don't understand how it works,” without having read it.
  • External standards and practices: we reinvent an exchange format, a naming convention or a process when a standard exists.

In management#

  • Methods from elsewhere: a practice from another company, another department or a book is rejected out of hand (“that wouldn't work here”), without a trial.
  • Hiring and consulting: a consultant's or a new hire's opinion is listened to less than a long-time colleague's, with equal content.
  • Relations between departments: one department refuses another's deliverables “because that's not how we do things,” and each builds its own tracking tool.
  • Team dynamics: teams that have worked together for a long time close themselves off to new ideas without realizing it.

Famous cases#

Study

A group's tenure and its isolation 1982#

Bias at play: NIH, isolation of the project group.

50R&D project groups studied
3organizations
1982published in R&D Management

What happened. Ralph Katz and Thomas Allen study the performance of 50 R&D project groups in three organizations. They find that, beyond a certain number of years of stability, groups communicate less with colleagues outside and with outside information, and that their results deteriorate. Long-standing groups become “self-sufficient” in their members' eyes, which is exactly the breeding ground of NIH.

What this illustrates

A very tight, stable group is efficient at execution and vulnerable to closing in on itself. Renewing perspectives (rotations, external reviewers, exchanges with other teams) is not a luxury for the curious, it is a measured protection against NIH.

Famous case

Procter & Gamble: from “not invented here” to “proudly found elsewhere” 2000-2006#

Bias at play: NIH, dependence on internal R&D.

~10% → over 50%share of new product inventions coming from outside, between 2000 and 2006
4.8% → 3.4%R&D as a share of revenue
~60%increase in R&D productivity

What happened. In the early 2000s, the American group Procter & Gamble finds that its R&D costs are rising faster than its revenue and that the pace of innovation is no longer enough. Under the leadership of CEO A.G. Lafley, it sets the goal that at least half of its innovations come from outside, and puts in place the “Connect + Develop” model (network of researchers, patents, partners). In Harvard Business Review in March 2006, Larry Huston and Nabil Sakkab report R&D productivity up by about 60%, an innovation success rate more than doubled, and R&D down from 4.8% to 3.4% of revenue.

R&D as a share of revenue (%)2000: 4.8%2006: 3.4%
Figures reported by Huston and Sakkab (HBR, 2006), for the year 2000 and then for the year of the article.

What this illustrates

The company did not stop doing research: it stopped thinking that only in-house research counted. Note that these figures are ones the company published itself; the decline in R&D as a proportion does not come solely from the open model. The reflex to remember: what you make is not better because you made it, and the cost of maintaining everything in-house eventually shows.

Counter-example

The left-pad counter-example March 22, 2016#

Bias at play: the opposite excess, uncontrolled dependence on an outside component.

11 linesof code for the function concerned
273packages removed from the registry by their author

What happened. On March 22, 2016, a developer, Azer Koçulu, removes all of his packages (273) from the npm registry following a dispute over a package name. One of them, left-pad, a function of about ten lines that pads a string on the left, is used, directly or not, by a very large number of JavaScript projects. The builds of many projects fail for several hours, until npm restores the package.

What this illustrates

Guarding against NIH does not mean importing without thinking. A dependency has a cost: availability, license, security, evolution. For eleven lines, writing and testing it yourself may be the right choice; for an encryption engine, never. The right attitude is to decide on criteria, not on provenance, in either direction.

Warning signs#

  • “We'd do this better ourselves” said before any evaluation.
  • The criteria applied to the outside product (maturity, support, security) are not applied to in-house code.
  • Several teams in the same company maintain equivalent tools.
  • The in-house development cost is compared with the purchase price without several years of maintenance.
  • The arguments against the outside solution are vague (“not suited to our context,” “we'd lose control”).
  • Ideas from newcomers or neighboring teams are received with condescension.

Avoidance reflexes#

  1. Apply the same criteria to both sides. Write the grid before the review (features, quality, security, license, cost, scalability) and score the internal solution and the outside solutions with the same grid.
  2. Cost the full picture. Development, testing, documentation, maintenance, upskilling, on-call: over three to five years, for building as well as for buying or reusing.
  3. Ask what sets us apart. Build what gives the product its own value; buy or reuse what is commonplace (authentication, logging, formats, scheduling).
  4. Test before rejecting. A short, bounded proof of concept is better than a judgment on paper.
  5. Open up the group. Cross-reviews with other teams, rotations, external presentations, regular watch: groups that exchange resist NIH better.
  6. Record the decision. Note the options, the criteria and the reason for the choice (an architecture decision record is enough) so it can be revisited.
  7. Reward reuse. Publicly recognize those who adopt someone else's good solution rather than those who rewrite.

With AI: detect, remedy, mitigate#

Estimated AI help: partial

AI is useful for broadening the state of the art and building a neutral comparison grid. But it does not know your context, may overlook recent solutions, and sometimes invents libraries or functions that do not exist. NIH is above all a cultural phenomenon: AI sheds light on it without dissolving it.

Detect#

  • Pick out, in a decision file, the asymmetric criteria between the internal option and the outside options.
  • Spot justifications without facts (“not suitable,” “too risky”).
  • List existing components for a given need, to be verified afterwards.

Fix#

  • Build a build / buy / reuse comparison grid with weighted criteria.
  • Estimate the full cost of each option over several years, with explicit assumptions.
  • Draft a proof of concept or a bounded test plan.

Mitigate#

  • Play the advocate for the outside option to force the group to answer point by point.
  • Summarize external watch (articles, release notes) to regularly feed the team.
  • Have the need reformulated without a solution, to avoid it already pointing to the in-house tool.

Prompts to build into your practice#

1. Build, buy or reuse grid. Before deciding to develop a component in-house.

We are considering developing [component / function] in-house. Help me compare three options objectively: build, reuse an existing solution (open source or commercial), or adapt an existing internal component.
1. Propose a grid of 8 to 10 criteria (features, quality, security, license, acquisition cost, 5-year maintenance cost, scalability, support, dependency risk, skills required).
2. For each option, say what we would need to know to score it, without inventing data: flag what you do not know.
3. Name families of existing solutions to examine, specifying that their existence and current state will have to be checked.

Context: [need, constraints, skills, expected lifespan]

2. Advocate for the outside solution. When the team dismisses a solution before evaluating it.

Here are the reasons why we are rejecting [outside solution]: [list].
Play the advocate for this solution. For each reason, say whether it rests on a verifiable fact or on an impression, what check would test it, and whether the same objection would apply to our internal solution.
Finish with the three cheapest trials that would settle the question.

How to build them in#

  • At pre-project stage: prompt 1 produces a grid that the team corrects and validates before choosing.
  • In an architecture committee: prompt 2 serves as devil's advocate on any decision to build.
  • In a retrospective: review the build decisions of a year ago, with their actual cost.

Precautions#

  • Check that the products, libraries and versions cited exist: an AI can invent them or cite abandoned projects.
  • Do not paste proprietary code, contracts or customer data into an unauthorized tool.
  • A grid produced by AI reflects common vocabulary; criteria specific to your context (regulation, hosting, sovereignty) have to be added by you.

Limits#

  • NIH is an organizational syndrome more than a measurable individual bias; the studies are mostly field surveys, whose results depend on context.
  • Rejecting an outside solution is not always NIH: security, license, sovereignty, migration cost or competitive advantage can be good reasons. The bias begins when the reason is provenance.
  • The opposite excess exists: depending on everything also means losing control (see the left-pad case), and a systematic taste for the outside falls under pro-innovation bias or the fashion effect.
  • The Procter & Gamble figures come from the company's own communications.

Sources and verification#

See also#

Combines with, or reinforces#

These biases feed each other.

Variants or cousins: not to be confused.

What neutralises it.