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FRM Exam Part II · Credit Scoring and Rating

Limitations and Criticisms of Credit Ratings

Updated 11 October 2026 · Fact-checked

Credit ratings are opinions on relative default risk, not precise probabilities. Their main criticisms are procyclicality (ratings and capital move with the cycle), issuer-pays conflicts of interest, slow adjustment to new information, and over-reliance in structured finance before 2008. Answer by naming the flaw, its cause, and its risk consequence.

Understand Limitations and Criticisms of Credit Ratings

A credit rating is an agency's opinion on a borrower's or instrument's creditworthiness, shown as a letter grade. Ratings are ordinal. AAA is safer than AA, but the gap in default probability between grades is not fixed or constant over time. Banks, investors and regulators use ratings for pricing, limits, eligibility rules and capital.

The first criticism is procyclicality. Agencies aim to rate "through the cycle", meaning they try to ignore short-term swings. In practice, downgrades cluster in recessions and upgrades in booms. If capital rules depend on ratings, as in the Basel II standardised approach and in ratings-based internal systems, downgrades raise risk weights in a downturn. Banks then need more capital just when it is scarce. They cut lending, which deepens the downturn. Point-in-time internal ratings are even more procyclical than through-the-cycle ones.

The second is conflict of interest. Under the issuer-pays model, the entity being rated pays the fee. The agency may be tempted to give favourable ratings to keep business, and issuers can shop for the best rating. The investor-pays model has its own problems, such as free-riding by non-subscribers. Structured finance made this worse. Agencies also sold advisory services on how to structure deals to get high ratings, which blurred independence.

The third is timing and accuracy. Ratings are slow to change. Agencies prefer rating stability, so ratings often lag market signals such as credit spreads, CDS spreads and equity prices. Enron, and sovereign downgrades in the Asian crisis, are typical examples of late action. Then downgrades come in large cliff effects, which trigger forced selling and collateral calls.

In the 2007-2009 crisis, many senior tranches of subprime mortgage securitisations and CDOs were rated AAA. Models relied on short data histories, rising house prices and low default correlation. When correlation jumped, mass downgrades followed. Investors treated a AAA structured product like a AAA corporate bond, although the risk profile differed: higher correlation sensitivity and larger tail losses. Remedies include less mechanical reliance on ratings, internal analysis, more transparency, and regulation of agencies.

How to solve Limitations and Criticisms of Credit Ratings questions

Use this method for any question on limitations of ratings. It works for scenario and definition items.

  1. 1Identify which limitation the question describes: procyclicality, conflict of interest, lag, or structured finance failure.
  2. 2Name the mechanism. For example, ratings-based capital rules link risk weights to the cycle.
  3. 3Note the rating philosophy if given: through-the-cycle is more stable, point-in-time is more responsive and more procyclical.
  4. 4State who is affected and how: banks cut lending, investors face forced selling, issuers shop for ratings.
  5. 5Check for cliff effects from rating triggers, collateral clauses or investment-grade mandates.
  6. 6Match the consequence to the risk concept: capital amplification, model risk, correlation underestimation, or information lag.
  7. 7Eliminate options that overstate, such as claiming ratings are always wrong, or that mix up the issuer-pays and investor-pays models.

Quickest way: Four-label shortcut

When to use it: Use when you have about one minute for a multiple-choice question.

  1. Label the scenario: cycle (procyclicality), fees (conflict), time (lag), or structure (2008 securitisation).
  2. Recall the one-line cause for that label: capital rules, issuer-pays, stability preference, or correlation and model assumptions.
  3. Choose the option that links cause to the right consequence.
  4. Reject options with absolute words like always or never.

Common mistakes in Limitations and Criticisms of Credit Ratings

  • Saying through-the-cycle ratings are more procyclical than point-in-time ratings.

    Students confuse the label with the aim of smoothing.

    Fix: Point-in-time ratings react quickly to conditions and so move more with the cycle. Through-the-cycle ratings are more stable, though they lag.

  • Blaming procyclicality only on agencies.

    The topic is filed under rating agencies.

    Fix: Much procyclicality comes from how capital rules and lenders use ratings. Risk weights rise in downturns when capital is scarce.

  • Treating the issuer-pays model as proof of deliberately false ratings.

    Textbook criticism is read as an accusation.

    Fix: Say it creates an incentive problem and ratings shopping risk. It is a conflict of interest, not proof of fraud.

  • Assuming a AAA structured product has the same risk as a AAA corporate bond.

    Same letter, so same meaning is assumed.

    Fix: Structured senior tranches depend heavily on default correlation and model assumptions, so they carry greater tail and downgrade risk.

  • Saying ratings lag because agencies lack data.

    Lag is attributed to ignorance.

    Fix: The lag is largely deliberate: agencies prefer stability and avoid reversals. Markets such as CDS spreads usually move first.

Worked examples

Example 1

A bank uses external ratings to set risk weights under the Basel II standardised approach. In a recession, many of its corporate borrowers are downgraded. Which statement best describes the effect and the criticism it illustrates?
A. Risk weights fall, capital is released, lending rises.
B. Risk weights rise, capital requirements increase, and lending may be cut, illustrating procyclicality.
C. Risk weights are unchanged because ratings are through-the-cycle.
D. Ratings are overstated because the issuer pays.

Show the solution
  1. Downgrades move borrowers into higher risk-weight buckets.
  2. Higher risk weights raise required capital for the same loan book.
  3. In a downturn capital is scarce, so banks may cut lending.
  4. Reduced lending worsens the recession: this is the procyclical feedback loop.
  5. A is the reverse effect. C ignores that downgrades did occur. D is a conflict-of-interest point, not relevant to the capital effect.

Answer: B

Example 2

Explain why AAA ratings on many subprime CDO senior tranches proved unreliable in 2007-2009, naming two causes.

Show the solution
  1. Identify the product: senior tranches of securitisations backed by subprime mortgages, rated AAA.
  2. Cause 1, model assumptions: ratings relied on short data histories and low default correlation among mortgages, with house prices assumed to keep rising.
  3. When house prices fell, defaults became highly correlated, so losses reached senior tranches.
  4. Cause 2, incentives: under the issuer-pays model, arrangers could shop for ratings, and agencies earned fees from structuring deals.
  5. Result: mass downgrades, cliff effects, forced selling by investors bound by rating mandates.

Answer: The ratings understated correlation and tail risk because of weak data and model assumptions, and issuer-pays incentives and ratings shopping reduced independence. When correlation rose, senior tranches were downgraded sharply.

Exam tips

  • Expect scenario questions: you read a situation and pick which criticism it shows. Name the mechanism first.
  • Know the through-the-cycle versus point-in-time contrast and which one is more procyclical.
  • Watch for absolute wording in options. Ratings are imperfect, not worthless.
  • For 2008 questions, link correlation, model risk and issuer-pays incentives together.
  • Remember cliff effects: rating triggers in contracts and mandates turn a downgrade into forced action.

Practice questions from Credit Scoring and Rating

Limitations and Criticisms of Credit Ratings in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Limitations and Criticisms of Credit Ratings: frequently asked questions

What is procyclicality of credit ratings?

It means ratings and rating-based capital requirements move in step with the economic cycle. Downgrades cluster in recessions, raising risk weights and capital needs when banks are weakest. This can reduce lending and deepen the downturn.

Why is the issuer-pays model a conflict of interest?

The entity being rated pays the agency, so the agency may fear losing business if it gives a low rating. Issuers can also shop around for the best rating. This weakens the perceived independence of the opinion.

Why do credit ratings lag the market?

Agencies prefer stable ratings and avoid frequent reversals, so they change ratings only when evidence looks persistent. Market prices such as credit spreads and CDS usually react earlier. The result is late and sometimes large downgrades.

What role did rating agencies play in the 2008 crisis?

They gave high ratings, often AAA, to senior tranches of subprime-backed securitisations. The ratings relied on models that understated default correlation. When housing fell, mass downgrades followed and investors suffered unexpected losses.