go downhill
Deteriorate, worsen, as in Ever since the recession began, the business has been going downhill. The figurative use of downhill for “decline” dates from the mid-1800s. Also see downhill all the way.
Related Words for go downhill perish, decay, disintegrate, warp, crumble, wither, spoil, molder, stain, decompose, languish, decline, dwindle, die, decrease, descend, fade, fail, depreciate, weaken