iOS becomes good a year after release, then Apple stops you from installing stable version, forcing install of unstable version with unwanted features.

What I tend to do is to only install/buy late in the yearly cycle, then stay on that for a year.

Good approach. Sadly, it only lasts a few months before iOS with maximum hardening (lockdown mode + Apple Configurator supervised) falls to another zero day. Then the only option is DFU reinstall, which forces unstable iOS install.

Perhaps I was just lucky, but 10.6.0 was equally stable as 10.5.8 for me. It did improve with time, and there’s little opposition to 10.6.8 being the best OS X release there was (except maybe 10.9.5), but for me at least it was a great OS even at launch.

I wish for snow leopard strategy to be applied to modern scaled operating systems. Let's all agree to spend a year fixing and optimizing rather than making existing functionality worse or launching half baked ideas.