“To make a long story short” is a commonly used idiom that signals that the speaker is about to summarize the information they are about to tell you. And the information doesn’t need to be a story — the phrase is commonly used prior to conveying all sorts of things that aren’t stories like an explanation or a conversation with someone else.

About 10 years ago I watched the fantastic South Park episode “I Should Have Never Gone Ziplining.” It’s pretty hilarious. The main theme of the episode is how lame ziplining is, especially for all the time and effort required to zipline. A sub-theme of the episode is that when people say “long story short” they often don’t make the story short. Here’s an 11-second compilation from that episode:

Since watching the South Park episode I’ve noted when people say “to make a long story short” and kept track of whether it seems as if they are really shortening the details of what they want to convey. Here are my conclusions based on my unscientific sampling:

• About 2/3rd of the time when someone says “to make a long story short” they aren’t signaling that they are about to summarize information but rather are letting you know that they are about to tell an overly detailed account of whatever they want to say.

• In modern usage, “to make a long story short” seems to be as much an advance apology that the speaker is about to tell a long story as it is a signal that a story is going to be abbreviated. It’s as if they realize they are about to give a lot of detail and they feel bad about it.

Maybe the problem is that it is hard to effectively shorten a long story. The etymology of the phrase “to make a long story short” is traced to Henry David Thoreau who wrote, “Not that the story need to be long, but it will take a long time to make it short.” Mark Twain expressed a similar notion when he wrote “I didn’t have time to write you a short letter, so I wrote you a long one.”

I can relate to the challenges of shortening what we want to say. The first drafts of the chapters of the book I’m writing on investment mental models often start at 10,000 or more words before I painfully cut them down by a few thousand words and then my editor chops off a few more thousand. It’s hard to say what you mean in an effective, succinct way.