Investor Corner/The wider picture/Investor Protection
5.4.2 Star Ratings and Their Limits
Fund star ratings are a useful first filter based mostly on past risk-adjusted return, but they say little about cost, portfolio quality, or whether a fund's history was actually earned by the manager currently running it.
What a star rating is actually built from
Star ratings, whether from a fund research platform or an AMC's own factsheet, are generally calculated from a fund's historical risk-adjusted return relative to its category peers over one or more trailing periods. A five-star fund has, by this specific measure, delivered stronger risk-adjusted returns than most of its category peers over the period examined.
Star ratings (typically on a 1-to-5-star scale) are assigned to mutual funds by rating agencies and platforms like Morningstar, Value Research, CRISIL and others. They provide a quick, standardised way to compare funds within a category. A 5-star fund has outperformed its category peers on risk-adjusted returns over the rating period; a 1-star fund has lagged. The convenience of a single number makes star ratings the most widely used shortcut for fund selection among retail investors.
What the rating does not tell you
A high star rating says nothing about the fund's current expense ratio, nothing about whether the manager who built that track record is still running the fund today, and nothing about how concentrated or overlapping its current holdings are with funds you may already own. A fund can carry a strong historical rating while having quietly become a considerably weaker choice for reasons the rating simply does not capture.
The primary limitation is that star ratings are backward-looking. They reflect past risk-adjusted performance, typically over 3-5 years. Research consistently shows that past star ratings have limited predictive power for future performance. A study of Morningstar ratings in the US found that 5-star funds subsequently outperformed 1-star funds on average, but the magnitude was modest, and a significant number of 5-star funds fell to 3 stars or below within a few years. High ratings tend to attract inflows, which in smaller fund categories can create challenges (larger AUM in small-cap funds, for example) that impair future performance.
Using ratings the way they are actually useful
A star rating is a reasonable way to narrow a large universe of funds down to a shorter list worth investigating further. It is not a reasonable basis for a final decision on its own, and checking manager tenure, cost, and portfolio composition after using the rating as a filter is what turns it into a genuinely useful tool rather than a shortcut that skips real diligence.
How PriLytics helps. PriLytics shows the real performance, cost and composition behind every fund you hold, giving you the fuller picture a star rating alone cannot. See holdings and returns.
Star ratings are best used as a screening tool, not a selection criterion. Filtering out 1- and 2-star funds reduces the probability of selecting a consistently poor performer. Among the 3-, 4- and 5-star funds, further analysis is needed: expense ratio, portfolio overlap with existing holdings, manager tenure and consistency, category suitability for the goal, and the fund's behaviour during drawdowns. A 4-star fund that held up well during the 2020 crash may be a better fit for a conservative investor than a 5-star fund that achieved its rating through concentrated bets that amplified both gains and losses.