as the time period gets longer, the the more likely it is that the numbers represent the true performance of the business rather than randomness. That has to be balanced against the fact that investors get less frequent updates i.e. the information is now potentially 6 months out of date rather than 3 months at worst. But then its just a judgment call of the relative benefit of each - you could argue that with modern accounting systems, modern companies could deliver weekly or even daily earnings , which would give investors much more timely information, and the high frequency would probably mean it wouldn’t be worth making the effort for management to fudge the numbers to bring forward or delay revenue one day or one week. There would be a lot more variance in the numbers if they were daily, but thats a good thing - it would just reflect the underlying randomness, and then the investors could decide when the accumulated trend over a period of time is meaningful or not, instead of management wasting time massaging numbers into a fairy tale of steady growth.