Suppose you have a scatch due to chain falling off, or other catastrophic failures.
or perhaps you want to run wires for your computer from back to front.
Solution is to use automotive outdoor vinyl to tape or mask things out. You can get those in any color on eBay, even carbon fiber patterns. This material lasts well, is easy to take off and replace, and is cheap. It will even protect your paint in case of chain failling off or some catastrophic failures when chain scrubs your frame. (will not help with chain slap because that happens too often)
Vinyl must be applied to the frame parts so that it is flat and there are no wrinkles. Use hair dryer for small wrinkles. For uneven frame surfaces you can use several smaller pieces of vinyl.
This is an exterimely useful solution for when you need to route wires under frame. Because exposed wires can get caught and broken. Vinyl will protect your wires.
I found that 3M adhissive used is not so good. It tends to separate at the ends. A solution is to use glue to glue vinyl to itself. Something that will not hurt your paint.
Among other things this mod adds to the look of your bike. It's cool to see parts of your chainstay and seatstay in carbon fiber look.