Saying that something is “good enough for government work” is often meant as a joke and the reference implies “mediocre work.” The irony is that “government work” is often highly sophisticated; systems are designed and engineered to operate in the most extreme environmental conditions for a very long period of time.
I recently had the pleasure of having lunch with a talented component engineer who has spent much of his career working in the defense industry. During the course of our discussion I learned that some aviation systems need ICs to operate in temperature extremes ranging from -55°C to 125°C; ground units often travel in harsh environmental conditions (e.g. fighting extreme heat and sand storms in deserts) while being exposed to hostile attacks; satellites traveling through orbit are exposed to protons and heavy ions from solar flares, yet must operate reliably in space.
The engineer’s narrative brings home the reality that focusing on “just getting the parts” in obsolescence management is far too simplified an approach. The big “total sustainment picture” is easily overlooked when dealing with budget restrictions, component obsolescence, and relentless testing, but boards need to be reliable; otherwise you will just have to keep scrambling to find replacements or risk a redesign.
If the program doesn’t require the board in question to navigate the cosmos or fly through the air like superman, or doesn’t need to last much longer than the embedded board’s EOL date, a refurbished board or a “buy-back” could be a viable option. However, “refurbished” means not always knowing whether a board is a new original board with minor repairs versus something completely rebuilt to be “like new” (sometimes without the original specs or test capabilities).
If something needs to be reliable in harsh environments, you might not want a board that has been pre-used, rebuilt, or has been sitting on a shelf in unknown conditions. Ideally, you want to know that everything is new, solid, and can be tested against the original specifications.