be (all) downhill | be ˌdownhill all the ˈway ( informal )
1.
to be easy compared to what came before :
It's all downhill from here. We'll soon be finished.
2.
to become worse or less successful :
It's been all downhill for his career since then, with four defeats in five games.
I started work as a journalist and it was downhill all the way for my health.