Course contents
Foundation · Course 1: What AI Can and Cannot Do · Lesson 3 of 5

The kinds of mistakes AI still makes and why

Level: FoundationTime: 40 minutesOrder used: A (the T-shirt)Tool: AI use worksheet
For anyone using an AI tool on repeated, routine work who wants to understand why the same tool that drafts and summarises well can also state a confident but wrong figure. Lesson 1.1 is useful preparation but not required. The case uses Order A and Cedar & Co.'s own domestic stock programme, and only approved master figures.
Domestic brandCedar & Co.
FactoryDelta Garments
OrderA — 15,000 T-shirts (figures reused)
FabricSingle jersey, 180 GSM, Ne 30/1
Reused FOB referenceUSD 3.20 per piece
Reused order value referenceUSD 48,000
02Opening

This page explains why an AI tool still makes specific, predictable kinds of mistakes, and why understanding the reason matters more than memorising a list of errors

An AI tool that drafts a clear email or summarises a long thread well can, in the very next request, state a wrong number, a wrong date or an invented detail with exactly the same confident tone. This is not a random flaw that will simply disappear with a better tool; it follows directly from how the tool produces answers in the first place, and it shows up on domestic stock work just as it does on export orders.

This lesson explains the underlying reason an AI tool makes these kinds of mistakes, using Delta Garments' own domestic stock work for Cedar & Co. as the case. Understanding the reason, rather than memorising today's list of known errors, is what lets you recognise a new kind of mistake tomorrow, on a tool you have not used before.

03Before you start

You need: the working idea of what an AI tool does from lesson 1.1 and the task-matching idea from lesson 1.2 are useful preparation but not required.

By the end of this lesson you can:

  • explain in plain words why an AI tool can state a wrong fact confidently;
  • name the kind of task where this risk is highest;
  • recognise why a routine, repeated task raises the risk of an unchecked mistake;
  • state why "it sounded right" is not evidence that an AI-generated fact is correct;
  • recognise the flow this lesson is about: information moving accurately inside the factory's own planning work.

Not covered here: how to fix or retrain an AI tool, or a technical explanation of the tool's internal design. Lesson 1.4 covers the practical method for checking an AI-generated answer.

04Key terms
TermMeaning
Confident wrong answerAn AI-generated response stated in a fluent, assured tone despite being factually incorrect.
Invented detailA specific fact, number or name an AI tool produces that was never supplied to it and does not exist in reality.
Pattern-based answerA response built from what commonly appears in similar text, rather than from the actual facts of your own situation.
Routine-task blindnessThe tendency to stop checking an AI-generated output carefully once a task starts to feel repetitive and familiar.
Source documentThe original record that holds the true version of a fact, which an AI-generated output should be checked against.
05Teaching
The rule

An AI tool produces the most likely-sounding answer to a request, and when it does not have the real fact, it still produces a fluent answer built from common patterns, which is why a confident tone is never proof of a correct fact

Because an AI tool works by predicting likely, well-formed text, it does not have a built-in way to say "I do not know this specific fact about your business" in the way a person naturally would. Instead, when asked something outside what it was given, it tends to produce the most plausible-sounding answer based on common patterns in similar text, delivered in the same confident tone as a correct one. This is the direct cause of most of the mistakes an AI tool makes: not carelessness, but the fact that fluent, pattern-based text and factually correct text look identical on the page.

FACT SUPPLIEDAnswer is built from the real fact givenFluent and correctReads the same as any other answerFACT NOT SUPPLIEDAnswer is built from a common patternFluent but possibly wrongReads the same as a correct answer
A confident tone does not distinguish a correct answer from a wrong one. Only checking the fact itself against a source document does.
What you meet in real life

The risk of an unchecked, confidently wrong answer changes with the task's repetition, the business model and who is checking

What can differThe shapes you will meetWhy it matters to you
Domestic replenishment under Make to Stock, factory sideDelta Garments' own planning team asks an AI tool to draft a weekly reorder summary for Cedar & Co.'s stock programme, week after week.A task repeated many times invites routine-task blindness: the tenth summary is checked less carefully than the first, even though the risk of a wrong figure has not fallen.
Export order under Make to OrderA one-off buyer query about Order A's specification is checked closely because it is unfamiliar and feels higher stakes.A task that feels novel gets more scrutiny by habit, which is one reason mistakes on routine domestic work are more likely to slip through unnoticed.
Hybrid order handled through an agentAn agent asking an AI tool to fill a gap in incomplete buyer instructions risks receiving a plausible but invented requirement.A gap in supplied information is exactly the condition under which a pattern-based, invented answer is most likely to appear.
A new user compared with an experienced userA new user may not yet know which of Cedar & Co.'s own figures are fixed and checkable, so an invented number can pass unnoticed.Recognising a source document to check against depends on knowing which facts in your own business are fixed; this knowledge is what makes the mistake catchable.
Different product familiesA knit-to-garment or terry order's own gauge, GSM or pile-height figures can each be invented just as easily as a T-shirt's fabric weight if the fact is not supplied.The underlying cause is the same across every product family: an unsupplied fact invites a plausible, unverified guess.
The case we follow

Delta Garments' planning assistant relies on an AI-generated stock summary for Cedar & Co. without checking it against the actual stock sheet

Cedar & Co., a domestic brand with 12 shops, buys from Delta Garments on a Make to Stock basis, reordering against its own sales forecast. Delta Garments' figures for a specific Cedar & Co. reorder are not part of the master figures used elsewhere in this course; for this lesson, the same fabric facts already fixed for Order A (single jersey, 180 GSM, Ne 30/1) are reused as the known, checkable reference the planning assistant should have compared the AI-generated summary against.

The planning assistant asks an AI tool to draft this week's reorder summary but does not paste in the actual current stock sheet. The tool returns a fluent, well-organised summary that states a plausible-sounding fabric specification. Because the summary reads clearly and the task feels routine after several weeks of doing it, the assistant sends it without comparing the stated specification against Delta Garments' own fixed fabric facts.

The worked number

An unchecked, confidently wrong specification costs far more to correct than the few minutes a comparison against the source document would have taken

Time to draft the summary with an AI tool, unchecked: about 4 minutes
Time it would have taken to compare the stated specification against the source fact sheet: about 3 minutes
Time actually spent correcting the wrong specification after Cedar & Co. queried it: about 45 minutes
Extra time caused by skipping the 3-minute check: 45 − 3 = 42 minutes
WITH THE CHECKCompare against fact sheet: 3 minutesWrong specification caught before sendingWITHOUT THE CHECKWrong summary sent to Cedar & Co.45 minutes spent correcting it later
Skipping the three-minute check did not save three minutes. It cost 42 extra minutes once the mistake reached Cedar & Co. and had to be traced back and corrected.
The method

Reduce the risk of a confidently wrong AI-generated fact in four steps

  1. Name the specific facts a task depends on before you ask the AI tool anything.
  2. Supply every one of those facts yourself, leaving no gap for the tool to fill with a plausible guess.
  3. Treat a routine, repeated task with the same checking discipline as a new one, since the risk of a wrong fact does not fall with repetition.
  4. Compare any stated fact you did not supply yourself against its own source document before it leaves your desk.
The trap

A common mistake is trusting an AI-generated output more, not less, the more often the same routine task has gone well before

A common mistake is assuming that because an AI tool has produced a correct-looking summary many times before, the next one needs less checking. The task itself has not changed; only the person's own attention to it has. The cost of that assumption is not visible on the ninth or tenth correct summary, only on the one time a gap in supplied information lets a plausible, invented detail through unnoticed.

06In plain words

An AI tool cannot tell you it does not know something the way a person can. Ask it a question it has the real answer to, and it answers well. Ask it a question it does not have the real answer to, and it still answers, just as smoothly, filling the gap with what commonly appears in similar text. The two answers read exactly the same on the page: the same clear sentences, the same confident tone, the same plausible level of detail. Only checking the actual fact against a real record, such as Delta Garments' own fabric sheet, ever tells the two kinds of answer apart from each other.

07Quick check
  • An AI tool cannot signal that it does not know a specific fact the way a person naturally would.
  • A fluent, confident tone is never evidence that a fact is correct, on an export order or a domestic one.
  • A gap in the information you supply is filled with a plausible guess, not a blank left for you to notice.
  • A routine, repeated task deserves the same checking discipline as a new one, since the risk does not fall with repetition.
  • The same underlying cause applies across every product family and business model, from a T-shirt's fabric weight to a towel's pile height.
08Workplace scenario

Cedar & Co.'s reorder note states a fabric weight the planning assistant never confirmed before sending it

The AI-generated reorder summary the planning assistant sent to Cedar & Co. states the reorder fabric as "190 GSM single jersey," a figure the assistant never typed into the tool and never checked against Delta Garments' own fabric record before sending.

  • Delta Garments' actual fixed fabric reference for this kind of order is 180 GSM single jersey, the same weight already fixed for Order A.
  • Cedar & Co.'s own buyer notices the mismatch against a previous confirmed order and asks Delta Garments to confirm which figure is correct.
  • The planning assistant has no note of ever supplying "190" to the AI tool.

Should Delta Garments confirm 190 GSM to Cedar & Co. because that is what the AI-generated summary stated? Decide before opening the answer.

Show decision

No. Delta Garments must confirm 180 GSM, its own actual fixed fabric reference, and correct the sent summary.

1. The 190 GSM figure was never supplied to the AI tool by the planning assistant, so it is a plausible, pattern-based number, not a checked fact from Delta Garments' own records. 2. 180 GSM is the fabric weight actually fixed and used in Delta Garments' own production, the same weight already confirmed for Order A, and is the only figure with a real source behind it. 3. Confirming the wrong figure to Cedar & Co. would cost far more to correct after fabric or costing decisions are made on it than the few minutes a check would have taken before sending.

The AI tool did not make an error in the sense of malfunctioning; it filled a gap it was never given the real answer to. The mistake was sending the result before comparing it against Delta Garments' own known figure.

09What it costs

An unchecked, confidently wrong fact on a routine domestic task costs time and trust in a way that scales with how far the mistake travels before it is caught

Order A's fabric reference used here for comparison is fixed at:

180 GSM single jersey, Ne 30/1 combed cotton (section 7 master figure, reused as the checkable reference)

A mistake caught before sending costs only the few minutes of the check. A mistake caught after it reaches a buyer, such as Cedar & Co. querying a mismatched specification, costs the time to trace the error, correct the record, and rebuild the buyer's confidence in the factory's own routine updates, as shown in the 42 extra minutes worked out above. The cost rises the further the wrong fact travels before someone catches it.

10Working template

AI use worksheet: record where a task depended on a fact you did not supply

Use the T18-C01 AI use worksheet. In the Risk log sheet, record each AI-generated output where part of the answer was not built from a fact you supplied, and note whether you compared it against a source document before using it. Start with the Cedar & Co. reorder example, then repeat the exercise for a task from your own week.

[Download the AI use worksheet](../../templates/T18-C01-ai-use-worksheet.xlsx)

Download the AI use worksheet (Excel)

11Check yourself

1. Why did the AI tool state '190 GSM' for Cedar & Co.'s reorder when Delta Garments' own fixed fabric reference is 180 GSM?

2. A domestic brand's planning team has used an AI tool to draft the same weekly reorder summary for six months without a single caught mistake. What does this history tell them about the risk of an unchecked mistake next week?

12Glossary
ENARFRTRMeaning
Confident wrong answerإجابة خاطئة واثقةRéponse erronée assuréeKendinden emin yanlış yanıtAn AI-generated response stated in a fluent, assured tone despite being factually incorrect.
Invented detailتفصيلة مختلقةDétail inventéUydurulmuş ayrıntıA specific fact, number or name an AI tool produces that was never supplied to it and does not exist in reality.
Pattern-based answerإجابة مبنية على نمطRéponse fondée sur un motifÖrüntü tabanlı yanıtA response built from what commonly appears in similar text, rather than from the actual facts of your own situation.
Routine-task blindnessتجاهل المهمة الروتينيةAveuglement lié à la routineRutin göreve karşı dikkatsizlikThe tendency to stop checking an AI-generated output carefully once a task starts to feel repetitive and familiar.
Source documentالمستند المصدرDocument sourceKaynak belgeThe original record that holds the true version of a fact, which an AI-generated output should be checked against.
13Next

Lesson 1.4: Checking an AI-generated answer before you rely on it

Next you will learn a practical method for checking an AI-generated answer before relying on it, seen through Meridian Sourcing's own use of AI on a hybrid order. Back to the course map

14Ladder

RecognizeState in plain words why an AI tool can produce a confident but wrong answer.
ConnectLink an unsupplied fact to the risk of a plausible, invented answer.
CompareTell apart a task where every fact was supplied from one where a gap was left open.
DecideChoose whether a routine task still needs the same checking discipline as a new one.