downhill all the way

downhill all the way

1. Bad and steadily worsening. Once my parents opened my report card and saw how bad my grades were, it was downhill all the way—not a great night for me.
2. Increasingly easy (as if one is literally traveling downhill, as opposed to uphill). I'm sure I can finish the rest of the experiment on my own—it's downhill all the way.
See also: all, downhill, way
Farlex Dictionary of Idioms.

downhill all the way

Also, all downhill from here.
1. Easy from this point, without obstacles the rest of the way. For example, Once we had the basic design, it was downhill all the way.
2. Deteriorating or declining from this point on, as in When the cancer couldn't be removed, it was downhill all the way for him. The usage therefore needs to be clarified by the context to indicate which of these opposite meaning is intended. The figurative use of downhill dates from the late 1500s. Also see go downhill.
See also: all, downhill, way
The American Heritage® Dictionary of Idioms by Christine Ammer.

downhill all the way

or

all downhill from here

COMMON
1. If a situation is downhill all the way or all downhill from here it continues to get worse until it ends. She came home, but it was downhill all the way. Cancer, I think. Now that I'm 50, it's all downhill from here. Note: You can also say that something is all downhill from there. The opening of the movie is great. Sadly, it's all downhill from there.
2. If a task is downhill all the way or all downhill from here, the most difficult part has been done and it is easier from that point. I had thought that once we reached halfway we would feel that it was downhill all the way now, but it didn't seem to work like that. With this game out of the way, it's all downhill from here because the remaining matches will be easy.
See also: all, downhill, way
Collins COBUILD Idioms Dictionary, 3rd ed.
See also:
  • be downhill all the way
  • as bad as all that
  • bad company
  • have a bad opinion of (someone or something)
  • have a good, bad, high, low, etc. opinion of somebody/something
  • it's the story of my life
  • story of my life, the
  • (it's/that's the) story of my life
  • have a bad night
  • have a good/bad night