A gap in a dot plot is a certain range where no data exists for certain values, thus, creates values more or less than the data cluster, which can be defined by the word outlier
Like the guy above said, it creates outliers. The reason behind this is because if there is a gap between two numbers that have a dot plotted on them, it means the numbers in between are non existent in the data, Which, in the end creates space between one number and the other which will create outliers
