go south
US /ɡoʊ saʊθ/
UK /ɡoʊ saʊθ/

1.
ir mal, dar errado, fracassar
to deteriorate, fail, or go wrong
:
•
Their business started to go south after the economic downturn.
O negócio deles começou a ir mal após a desaceleração econômica.
•
The plan seemed good at first, but then everything started to go south.
O plano parecia bom no início, mas depois tudo começou a dar errado.