I don’t understand why the NoKos can’t do this successfully, unless their engineering is hopelessly flawed, in which case they shouldn’t be staging these pie-in-our-own-face circuses. Some things are just difficult. You can't simulate everything (such as the effects of vibration, thermal shock loads, timing issues on separation, etc.). The US had a couple of dozen failures in our early rocket program. Remember Vanguard?
- Vanguard TV3 - December 6, 1957 - Failed to orbit 1.36 kg (3 lb) satellite
- Vanguard TV3 Backup - February 5, 1958 - Failed to orbit 1.36 kg (3 lb) satellite
- Vanguard 1 - March 17, 1958 - Orbited 1.47 kg (3.25 lb) satellite
- Vanguard TV5 - April 28, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
- Vanguard SLV 1 - May 27, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
- Vanguard SLV 2 - June 26, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
- Vanguard SLV 3 - September 26, 1958 - Failed to orbit 9.98 kg (22 lb) satellite
- Vanguard 2 - February 17, 1959 - Orbited 10.8 kg (23.7 lb) satellite
- Vanguard SLV 5 - April 13, 1959 - Failed to orbit 10.3 kg (22 lb 11 oz) satellite
- Vanguard SLV 6 - June 22, 1959 - Failed to orbit 10.3 kg (22 lb 11 oz) satellite
- Vanguard 3 - September 18, 1959 - Orbited 22.7 kg (50 lb) satellite
The joke was that Vanguard was like a government worker: 'You can't fire it and you can't make it work.'