| mar(verb, decline, weaken, degenerate, deteriorate) |
| miss the mark(verb, expression, idiom, decline, fall) |
| pervert(verb, decline, weaken, degenerate, deteriorate) |
| peter out |
| poop out |
| recede(verb, drop, decline, fall, fail) |
| regress(verb, decline, weaken, degenerate, deteriorate) |
| relapse(verb, drop, fall, fail, diminish) |
| retrograde(verb, drop, decline, fall, fail) |
| retrogress(verb, decline, weaken, degenerate, deteriorate) |
| return(verb, drop, fall, fail, diminish) |
| revert(verb, drop, decline, fall, fail) |
| run down |
| sag(verb, drop, fall, fail, diminish) |
| settle(verb, drop, fall, fail, diminish) |
| shrink(verb, drop, fall, fail, diminish) |
| skid(verb, decline, weaken, degenerate, deteriorate) |
| touch bottom |
| undermine(verb, decline, weaken, degenerate, deteriorate) |
| vitiate(verb, decline, weaken, degenerate, deteriorate) |