French phrase
Je ne vois pas pourquoi je devrais ~.
Meaning
I don't see why I should ___.
When to use it
A direct way to refuse a request. It can sound blunt or cold, especially with familiar people.
Example dialogue
Tu peux m'aider à déménager samedi ?
Can you help me move on Saturday?
Je ne vois pas pourquoi je devrais t'aider.
I don't see why I should help you.