Hardly unique to writers, I've had much of the same issues with procrastination when working on personal programming projects. Much as they describe writer's fear of writing a bad novel, I give up when I think no one will want to use the app I'm working on, I think the project be too difficult to finish, or I'm worried about letting people see my badly written code.
Obviously there are some differences - there's a more specific barrier to making software that is functional serves it's intended purpose, compared to a story that might be badly written. But I think "I'm working on an app" may be our generation's version of the "I'm writing a novel" cliche