Reading my paperback books, I am always amazed at the typos and grammatical errors that often happen between the pages. Sometimes, it seems like they are adding/subtracting words or misspelling them in order to "fit" on the page and make even lines on the page.

Is that their number priority, making the lines pretty, or is just awful editing skills on the publisher's part?

I remember when my local newspaper would "stretch out" lines with extra spaces in order to make the column pretty.