The problem is that you are only as strong as your weakest link. At some point, something somewhere will be architected poorly and it will one day line up perfectly with 2 other bugs that were incredibly hard to predict and then you're stuck in Microsoft's current situation.

Also, power grids are a poor example. There's been multiple instances of absolutely catastrophic failures so hoity toity capital E Engineers also make mistakes.

https://en.wikipedia.org/wiki/2025_Iberian_Peninsula_blackou...

https://en.wikipedia.org/wiki/Northeast_blackout_of_2003