It's not specifically for me building an app it's for a User Guide I'm putting together for our content on our company's website. That being said, in what speci

It's not specifically for me building an app it's for a User Guide I'm putting together for our content on our company's website. That being said, in what specific situation would it be useful to use a backend service and what type of situation would make it better to create your own? Or does this depend more on the developer's experience maybe? I'm also interested in cost differences overall.