When developing a website, there are certain CSS practices which simplify your life. For instance, adding comments and indents makes your code easier to read and understand. This makes editing or altering your code much easier – something which can make you more productive.
However, the extra spaces and characters also contribute towards the size of the CSS file. A CSS file with lots of comments – for instance – tends to be quite large and heavy. This makes the CSS file to load slowly – something which slows down the overall loading time of a webpage.
Therefore, before deploying a CSS file, it is often advisable to optimize its loading time. This basically means reducing its overall size so that it loads faster. The process by which you do this is CSS minification.