If you do this, then you will never be able to have multiple floated div
s stack horizontally with one another, because your clearfixes are getting in the way.
So in a way, having a clearfix on every div
element would nullify the effect of floating them, as well as related elements.
This is why articles often suggest applying clearfix to a certain class, then giving the desired elements that class instead:
.cf:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}