(Quoting Dan Geer:)
"...around here, rust lowers it pretty good, and real reliably

the driver seat in my '64 bug lowered itself a good 6 inches
and the whole front end of the '73 squareback lowered about 4.

and then there's the time i couldn't restart the '66 after a
taking a break in a multihour drive over Maine logging roads
and i eventually figured out that the battery had lowered itself
right out of the car. "

-And then there's the instant lowering of rear when axle tube rots out (my
71), and the garanteed 20 deg. of free play when steering arm bushing
housing  rots way!     Mike Benthin in NJ