One reason you may have low disk space is that you are not using it to its fullest potential. You may be using it for things that you don't really need, such as downloads or photos. You may also be using it for things that you don't want to delete, such as pictures from your childhood that you keep on your computer but don't use anymore. By deleting these pictures, you are freeing up disk space so that you can use it for things that you really need.