Bad Thing [from the 1930 Sellar & Yeatman parody "1066 And All That"] n. Something that can't possibly result in improvement
of the subject. This term is always capitalized, as in "Replacing
all of the 9600-baud modems with bicycle couriers would be a Bad
Thing". Oppose Good Thing. British correspondents confirm
that Bad Thing and Good Thing (and prob. therefore {RightThing}
and Wrong Thing) come from the book referenced in the
etymology, which discusses rulers who were Good Kings but Bad
Things. This has apparently created a mainstream idiom on the
British side of the pond.