“Show, don’t tell”, right? Why tell the reader about a past event when I can literally take them there?
A full-scene flashback occurs when the story shows the past by giving it its own scene instead of integrating the information into the basic narrative.
While it can be beneficial for readers to see backstory in some circumstances, backstory is backstory for a reason and full-scene flashbacks aren’t needed as often as they can be used. They can be a fun way to introduce past information, and if used correctly are a great addition to a story, but not all information deserves the kind of attention that the narrative tool grants.
Full-scene flashbacks are not inherently bad, but it’s important to understand that they aren’t just fancy scenes to throw in to make something “better”. They have direct effects on a scene and story because they’re a narrative choice and not all stories benefit from the consequences that adding them can create.
“Show don’t tell” is definitely a strong guideline to follow, but part of bettering writing skills is learning when “showing” actually hurts your overall narrative. Poorly-used flashbacks are a quick way to burden your story, so it’s probably good to learn more about them.
(Note: This post does not cover “special circumstances”, like stories specifically built to parallel the past/present or characters who experience true traumatic flashbacks. This is about how full-scene flashbacks can affect a general story.)