“These people dropped out of college and ended up having very successful careers in their fields. Should I too?”
In statistics, an outlier is a data point that differs significantly from other observations.
Many sets of data follow the so-called “normal distribution.“ In a normal distribution, data follow a symmetric, bell-shaped curve, in which most values are located near the center (i.e., the mean). That is:
Around 68% of all observations fall within one standard deviation.
Approximately 95% of all observations fall within two standard deviations.
Nearly 99.7% of all observations fall within three standard deviations.

While the mean refers to the sum of values divided by the number of values, the standard deviation (σ) measures the amount of variation or dispersion of a set of values.
For instance, a low standard deviation indicates that the values tend to be closer to the mean of the set, while a high standard deviation indicates that the values are spread out over a broader range.
Anything that is not within 95% of values is an outlier. That is, chances of that value happening are uncommon.
Here is an example:
In 9th grade, I failed the last math term. To my surprise, the retake exam in June comprised the entire syllabus and not just what I had learned during the term. To make matters worse, my teacher told me that no student had ever passed that exam in June since he began teaching at my school. That meant I would likely have to spend the summer studying to retake the exam in September. Since I did not want that, I told myself I would still try and pass the exam in June. And I became the first-ever student to pass that exam!
I was an outlier because I learned years later that instead of “no one ever passes that exam,” the teacher was now saying, “only one student passed that exam.” Statistically, the more students take that exam, the more chances that there will be another outlier.
Still, because chances of passing that exam are meager, passing students will always be the exception.
That is why I want you to bear in mind the following:
While we all know some of the most successful business people are college dropouts, those people are outliers. If we look at the bigger picture, the truth is that for every highly successful college dropout, hundreds of others end up wishing they had finished school.
However, if you genuinely believe you will be that outlier — like I did when I had to retake Math — I encourage you to pursue your goals. No matter what the result is, you will learn a valuable lesson!