I mean there's both that, and that thing when where "deleting" a file doesn't actually take the bits and make them zero, but just marks them as available to the computer, so until they're overwritten they're still technically there.
I always thought I was a bad writer for not being able to think of these small details, and that it feels like you just have to push/force yourself – which I probably still am, but it's comforting to know that that feeling isn't uncommon.
I recently bought a brand of wrap that has a slider that cuts it. Sort of like a zipper. Helps a lot since it's easier to put it over whatever you're wrapping beforehand.