From First to Thinnest in Less than 10 Years: Swiss Quartz started with Beta21 (top) in 1970 and reached perfection in the category miniaturization in 1979 with the ETA cal999 Delirium Tres Mince (bottom).
As you know we see only two relevant categories in quartz: miniaturization and precision -- both were reached in the 70s, already.
Now, thats an interesting high-speed development. And so we understand this speed is not for everyone: If your comfort zone is 3Hz and you become nervous at 4Hz-Mechanical-Movements, already, then 300Hz Tuningfork-Movements simply arent healthy for you and 32'768Hz Quartz probably really dangerous. For all others: There is a lot to see in the sphere of electronic watches 1961ff.