In what sense is journalism itself an act of critical thinking?

Good journalism questions everything, continuously, at every stage — during research, during production, and even after publication — including a journalist's own work.

The craft is critical thinking applied as a daily discipline rather than a one-off check:

• Question everything, everywhere, every single step — no claim is waved through.
• It runs across the whole pipeline: during research (is this true?), during production (is this framing fair?), and after publication (did we get it right?).
• It turns inward: journalists are expected to examine their own pieces critically and sustain a feedback culture where colleagues challenge each other.

The point is that scepticism isn't reserved for sources — it is also aimed at oneself, which is what keeps the watchdog from becoming careless.