I don't get the point of these types of "5 levels of X"...
Like yes you can take any continuous variable and draw as many lines in the sand as you'd like (5 levels of tallness, or even 27 levels of tallness, or whatever) and actually say nothing while apparently sound like you're saying something??
They're massively overused, but sometimes continuous variables cause effects that are more discrete in nature. Like, sizes of human torsos follow the normal distribution, but t-shirts come in a few very much discrete sizes, so at some point it makes sense to make a simplification that in certain contexts, torsos themselves have a few discrete sizes.
Like yes you can take any continuous variable and draw as many lines in the sand as you'd like (5 levels of tallness, or even 27 levels of tallness, or whatever) and actually say nothing while apparently sound like you're saying something??