What's amazing is that the K-25 uranium enrichment plant (gaseous diffusion) was literally slapped together as quickly as possible, in about a year and a half, designing and redesigning as they went along...there was a war to win, after all, and we were terrified someone else would get there first. Despite that, the plant ran reliably for over 40 years. I doubt that anyone ever considered that this thing would be capable of running for decades. It was really an engineering masterpiece.