Wikipedia says, “A paragraph is a self-contained unit of a discourse in writing dealing with a particular point or idea. This includes at least three sentences. The start of a paragraph is indicated by beginning on a new line. Sometimes the first line is indented. At various times, the beginning of a paragraph has been indicated by the pilcrow: ¶.”
In applications like InDesign, a paragraph is any discrete block of text that needs to be separated from those around it. Paragraphs as defined are an example. So are all heads of various levels, and list entries. Publishing software is set up with the assumption that these will end with a pilcrow, the paragraph return, and that paragraph returns will appear nowhere else. Otherwise, basic functionality such as style sheets cannot work correctly.
There are three common ways in which you might find paragraph returns misused:
- To position text.
- To create paragraph space, or
- To break lines within a paragraph.

All three of these usages present more or less the same problems. Because returns are not uniform in size, using them to position text or create relationships between blocks of text or other elements is imprecise and difficult to duplicate. Working this way, elements that appear throughout a document will be inconsistent because every instance is a kludge. Space above and below paragraphs must be created within the style sheet using the space above and space below properties. The position of a block of text should be achieved using the text-box alignment properties or by appropriately sizing and positioning the text box.

Creating line breaks with returns is an even more problematic misuse of paragraph returns. Inserting a paragraph-ending return within a paragraph creates two paragraphs. So, the second paragraph must have its style changed to make it appear to be part of the paragraph above. There is a forced line break character intended for this purpose. However, if you are manually breaking hundreds of lines in a document instead of, for example, unchecking the Hyphenate box in the style sheet once, what are you doing?
If you use returns in any of these ways, you create a document that is much harder to work with. Design changes that apply to elements spaced or positioned with returns require that you revisit and redo every instance instead of making one change to a style sheet. Text edits that cause kludged paragraphs to reflow can produce typographic messes that add hours to production time.
There is another drawback to using empty returns in a document. Every one of those returns has paragraph attributes of its own, including style, size and font. While these varying attributes make the returns problematic as formatting elements, they also introduce fonts and styles that may not appear anywhere else in the job, confusing the document’s design and output. Jobs or portions of them routinely get picked up from other jobs. If the picked-up content is not reconciled with the current design, you will soon end up with a job full of extra fonts and styles. Empty returns are a place for such problems to hide.
