It's a slippery slope.

Translation language

Meaning

Taking a particular action will inevitably lead to a series of negative consequences.

John: 'Let's relax the regulations a little.'

Alice: 'It's a slippery slope; we could end up with total deregulation and chaos.'

John: 'It's a slippery slope; it could lead to widespread censorship and the suppression of free speech.'

Alice: 'Let's censor this one post.'