system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If IQ is standard deviation, why isn't there a ceiling that no IQ can surpass?
gpt
Standard deviations, and by extension, normal distribution, tell you data is likely to be distributed, but it doesn't impose limitations.

In fact, if data has a perfect normal distribution, it *can't* have ceiling, because the normal curve extends to infinity in both directions.  At it can tell you is how unlikely it is for very high or very low values to be included in your data set.