one step forward and two steps back
It is a popular lyric to a song, but sometime used i phrases or as comparisons to things. it's basically taking one step back. and it means, making progress towards something but making less progress rather than more, if that makes sense.
"one step forward < two steps back"
"one step forward < two steps back"
I was trying to finish my math homework, and i did the beginning, but going to that party before finishing was one step forward and two steps back.