For example, imagine a worker in a widget factory who is responsible for checking if all the widgets on a conveyor belt are well-made. This worker is successful in their job 99% of the time. However, when a second worker is added to the same task, and both workers are aware of the other, the accuracy rate drops to 90% because both workers assume that the other person will do a good job.

Is there a word or phrase to describe this phenomenon? It's related to "bystander effect" but not exactly it.

  • 1
    Soomething you might want to look into: Diseconomies of scale. Describes the phenomenon that from a certain point onward, an addition of productive resources to an economic undertaking does not add but rather removes utility.
    – l337n00b
    Commented Jan 10, 2023 at 7:41
  • There is the law of diminishing returns, but this is somewhat different. Commented Jan 11, 2023 at 16:51
  • Seeing that the answers are split between idiomatic expressions and economic / business jargon, you might want to specify what type of answer you are looking for.
    – Kirt
    Commented Jan 11, 2023 at 18:14
  • 1
    Sounds like a case of 'too many cooks'. That is a shortening of the proverb that is clearly recognised in the abbreviation not mentioning the spoiled broth.
    – Tuffy
    Commented Jan 15, 2023 at 22:33
  • Erm... normal? Job-sharing might suit some workers, but it's almost always gonna be more expensive / less efficient from the empoyer's perspective. Commented Jan 2 at 20:17

10 Answers 10


Since you mention the "bystander effect", I guess you're looking for a psychological term. This would be "Diffusion of responsibility", even though its prime examples are mostly taken from emergency situations:

The diffusion of responsibility refers to the decreased responsibility of action each member of a group feels when they are part of a group. For example, in emergency situations, individuals feel less responsibility to respond or call for help if they know that there are others also watching the situation - if they know they are a part of the group of witnesses

Further down the article, both "bystander effect" and "social loafing" (as mentioned by JonathanReez) are listed as two possible consequences of diffusion of responsibility.

  • 1
    This seems like the best fit for OP's question.
    – Tom
    Commented Jan 10, 2023 at 0:21
  • What do you call it when this diffusion of responsibility is intentional and used as an excuse to let someone die? Good examples are (1) The rainmaker, a novel by John Grisham adapted into a film with Matt Damon, and (2) two awful true stories from 2021 and 2022 about British and French coast guards refusing to rescue drowning migrants despite the repeated radio calls for help.
    – Stef
    Commented Jan 10, 2023 at 14:51
  • 1
    @Stef A "lame excuse", punishable due to "failure to assist a person in danger".
    – orithena
    Commented Jan 10, 2023 at 15:08

This sounds like a case in which too many cooks spoil the soup.

This means, according to The Free Dictionary:

If too many people try to control, influence, or work on something, the final product will be worse as a result.

  • 42
    I have always heard this as "too many cooks spoil the broth". Google ngram suggests it has been the more common expression since at least 1800.
    – Peter
    Commented Jan 9, 2023 at 7:36
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    This idiom is used when people show overinvolvement in an activity/task(thus botching up the whole thing), rather than tacitly assuming the other person to carry it out.
    – user405662
    Commented Jan 9, 2023 at 10:51
  • 2
    @Peter It's interesting. Looking it up, I found the same thing. But I've heard the "soup" version a lot more often. Maybe it's a regional thing?
    – alphabet
    Commented Jan 9, 2023 at 13:05
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    I've only ever heard 'broth' - but cunningly countered by 'many hands make light work'. UK, maybe?
    – Tim
    Commented Jan 9, 2023 at 14:21
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    @Peter We would just say "too many cooks in the kitchen". (Although it's different from the example the OP gives, since none of the "cooks" are presumed to be slacking...just that they are getting in each others way.) Commented Jan 9, 2023 at 15:14

There is a term in software development called Brooks's Law. The idea is that adding additional personnel to a project will increase, not decrease the time it takes to complete it.

The idea is typically that the overhead of adding more people to the task is more work for the people already engaged in the task, increases the burden of communication as you don't want to make changes that impact other's work, and that knowledge of the entire system is necessary to begin working and thus the task is largely non-divisible anyway.

I've never heard it referenced outside of software development but unlike other answers doesn't come with the implication that the people involved are just doing sloppier work, its just a feature of the task.

  • 4
    I understood the question as asking about the name of an effect that precisely involves people doing sloppier work because they know that they are not the only responsible person. Still, this answer has value in case I misunderstood the question.
    – orithena
    Commented Jan 9, 2023 at 14:34
  • 1
    Well, the questioner said it was "related to bystander effect" but not exactly it. Your answer is closer to a synonym whereas mine is related but distinct. I think both have value but no one had taken my angle yet.
    – richarjt
    Commented Jan 9, 2023 at 14:45
  • Well, yes, "bystander effect" describes "people not _re_acting because they're in a group", while the question asks for "people not acting to their full potential because they're in a group". In the first case, they're not yet involved (as "bystander" suggests); in the latter, they are already involved. I think that was the motivation to mention the "bystander effect".
    – orithena
    Commented Jan 9, 2023 at 14:51
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    Related: "The Mythical Man-Month: Essays on Software Engineering". Specifically the term "Mythical Man-Month".
    – KDecker
    Commented Jan 9, 2023 at 15:29
  • 3
    Brooks uses the analogy of putting more women on the job to have a baby in 3 months. And that shows how "job" has many meanings, not all of which are countable. Commented Jan 9, 2023 at 16:04

I think the right term is social loafing, which Wiki defines as:

Social loafing is the phenomenon of a person exerting less effort to achieve a goal when they work in a group than when working alone. It is seen as one of the main reasons groups are sometimes less productive than the combined performance of their members working as individuals.

  • 1
    +1. I learned something new today! But for it being jargon (which might be okay for the OP's purposes), this is exact. Commented Jan 9, 2023 at 2:34
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    It's worth noting that this is a specific aspect/manifestation of the "tragedy of the commons". Commented Jan 9, 2023 at 10:09
  • It's worth noting that "tragedy of the commons" was propaganda. Commented Jan 11, 2023 at 17:34
  • @CodyGray As I understand the "tragedy of the commons", it is when producers are incentivized to over-use a public resource because the results of their production are privately held. Other than there being "too many" of something, I don't see how that applies at all to OP's posit.
    – Kirt
    Commented Jan 11, 2023 at 18:12
  • 1
    The term is not nearly that specific, @Kirt. It generally refers to the phenomenon where people who have unfettered access to a resource tend to act independently according to their own self-interest and, thus, contrary to the common good. In this way, they exploit and deplete the "commons" (shared resource). In social loafing, one actor essentially assumes that someone else will do the work (produce the shared resource), thus they don't do anything (selfishly exploit the limited resources). As to whether it's propaganda…that's a matter of perspective and ultimately irrelevant. Commented Jan 12, 2023 at 6:33

I upvoted "too many cooks spoil the broth (or soup)" because I think it most closely matches the paradoxical effect of reduced efficiency from adding people to a task.

I also thought of the Bystander Effect, but as I understand it, that effect is usually brought up about others who just stand around and do nothing - rather than doing the same thing less efficiently. But I also see that it could be used to refer to reduced efficiency or to people who want to be helpful but end up being no help due to the effect of others around them.

"Passing the buck" or "diffusion of responsibility" don't sound fitting for this kind of concept, as far as I see it. Those terms are focused mainly on people who are deliberately avoiding certain work, as opposed to two people honestly trying to do a good job but suffering a drop in efficiency as a side-effect of being put on the same task.

Finally, there is the concept of the "mythical man month." This term is from a book on software development, so it is not useful to anyone who doesn't follow software or project management jargon. But it does capture the idea that adding people to a project tends to make that project even later. This concept, however, is about training and other overhead, not about one worker assuming another will do the same task, as is presented in the question's scenario.

Therefore, assigning more programmers to a project running behind schedule will make it even later. This is because the time required for the new programmers to learn about the project and the increased communication overhead will consume an ever-increasing quantity of the calendar time available


  • 1
    I don't think mythical man month applies here. In that case, the extra worker is doing the same general job as the other workers, i.e. "software developer", but the specific job is different, i.e. "developing component X" where the other workers are "developing component A", "developing component B", and so on. The extra cost comes from the increased communication required amongst all the developers. But in this question, the two workers are doing exactly the same job, i.e. "checking all the widgets for defects", which does not require any intercommunication at all. Commented Jan 10, 2023 at 2:49
  • Thanks John, I agree. I also realized that "too many cooks" can also have a pejorative connotation (as in, each cook thinks they can do it best), but in general I think it best matches the question's request.
    – jrdevdba
    Commented Jan 10, 2023 at 21:09
  • 2
    I would point out the term isn't from the book, the book is named after the term. It's a management term, where managers say a project will take X man-months or Y man-years of labor, making or eliding several false assumptions: (1) That humans are equally interchangeable, (B) that all the labor is parallelable (i.e. that one man's work isn't dependable on someone else finishing their work first), (C) that adding additional people doesn't have time-costs (i.e. training, as you pointed out), and (D) that adding additional people doesn't have communication/coordination/management time-costs.
    – Jamin Grey
    Commented Jan 10, 2023 at 22:35
  • en.wikipedia.org/wiki/Man-hour
    – Jamin Grey
    Commented Jan 10, 2023 at 22:42
  • Thanks Jamin. I haven't read the whole book, so I appreciate the context that you added.
    – jrdevdba
    Commented Jan 11, 2023 at 21:14

This is also known as the law of Diminishing Returns

For example, the law states that in a production process, adding workers might initially increase output. However, at a certain point the optimal output per worker will be reached. Beyond that point, each additional worker's efficiency will decrease because other factors of production remain unchanged, such the available resources.

Source: TechTarget

  • 7
    No, the law of diminishing returns is something different. OP is asking about the case when two people together are less productive, or less accurate, or less desirable in some other way, than just one person. The law of diminishing returns is when two people are less than twice as productive as one person. Commented Jan 10, 2023 at 0:28

Less than the sum of its parts

The expression "greater than the sum of its parts" describes a situation where the combined efforts of two or more individuals exceed the sum of the capabilities of each individual. From collinsdictionary.com:

If you say that something is more than the sum of its parts or greater than the sum of its parts, you mean that it is better than you would expect from the individual parts, because the way they combine adds a different quality.

This is often used with relation to pop groups - also from collinsdictionary.com:

As individual members' solo careers have proved, each band was greater than the sum of its parts.

Accordingly, "less than the sum of its parts" is understood to describe a situation where the combined efforts of two or more individuals are less effective or of lower quality than you might expect, given the capabilities of each individual.

Revisiting the pop group example, this expression might be used where two or more successful / talented solo artists collaborate to produce a piece of music, which is judged to be underwhelming. (Naming no names...)


“Asynergy” is actually a word with the meaning “ defective coordination between parts” (https://www.collinsdictionary.com/dictionary/english/asynergy) but it has apparently been hijacked by the medical profession. Still, its meaning would be clear, and its use outside medicine could be justified as metaphorical. Similar remarks apply to “dyssynergy”.

If you prefer a less tainted word, then “anti-synergy” would be more than acceptable, not least because others have found it so - e.g.https://brill.com/abstract/book/9781848883574/BP000003. xml


The correct term is, TRAINING YOUR REPLACEMENT. When a second person is added to do the job that you were able to handle on your own, the most common sense reason for why they are there is to replace you. This will cause much dissatisfaction and resentment on the part of the initial worker, and tension between them both.

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    – Community Bot
    Commented Jan 11, 2023 at 20:20

Well, in the latter case the buck doesn't stop with either one of them. So the word/term is mutual Buck passing.

Also, The Farlex Dictionary gives this idiom for such a situation:

pass the baton

To bestow one's responsibility or job upon someone else. [An allusion to a relay race in which one runner literally hands a baton to the next runner.]

I have so much work to do now that my boss has retired and passed the baton to me.

pass the baton

  • 11
    "Passing the buck" has rather negative connotations; if someone does it, it's usually hurting someone else. "Passing the baton," on the other hand, is something expected to happen and has positive (you're replacing a tired runner with a fresh one), or at worst neutral, connotations.
    – cjs
    Commented Jan 9, 2023 at 12:27

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