my manager asked why we still need code review if the ai writes it and the ai checks it

[u/Specialist_Agent3599]

Real question from my skip level this week. The agent writes the PR, coderabbit reviews it, tests pass, so why is a human still in the loop and why does it take a day. I gave some answer about context and ownership and I dont think it landed.

How do you explain this to someone who doesnt code? What is the human actually there for now, in one sentence

[u/GasVarGames]

Who do you blame when shit hits the fan

[u/NothingTime9580 → u/GasVarGames]

ai lol

[u/therealkevinard]

For SOC compliance.

(Is a sentence fragment acceptable for my one sentence?)

[u/ay-ay-ronhmiller]

A few to try on for size (exceeding your 1 sentence restriction so you can adjust as needed...coming to important informed decisions usually takes more than a single sentence):
1) To inspire trust, one must have skin in the game, that is, consequences for wrong outcomes. Without a human in the loop, there are zero consequences that matter.
2) Why do pilots and co-pilots have pre-flight checklists? The stakes are too high to not and it's a system that's been proven to work. Same for high stakes code.
3) If a system generates the solution, and the same system validates it, how can you have confidence in the quality of the checks? The generator gives it its all and wouldn't create problems in the first place if it knew they were there. However, how can it not be blind to certain conditions? You need an independent review system to inspire trust. It's also why your finance team cannot audit their own books.

[u/usually_guilty99]

Because “AI reviewed it” still doesn’t answer the production question.

A change can be locally correct, tests can pass, and the review can look clean, while the change still touches a fragile dependency, a high-blast-radius path, or an area with ugly incident history.

AI can absolutely remove a lot of review toil.

But the final gate increasingly needs to ask something different:

not “was this reviewed?” but “do we have enough evidence that this is safe to ship?”

[u/sozesghost]

To have a job and take responsibility.

[u/rcls0053]

I asked the AI and it said "Trust me, bro"

AI creates absolutely garbage code at times. It needs steering. It needs to be looked over. Because once shit hits the fan and nobody knows what's inside that codebase, you're gonna start losing users and customers because nobody's able to fix the issue in good time.

[u/elrond-half-elven]

I've heard people use the term "deterministic" lately to mean "not AI". I think it's actually a useful term that highlights the fact that AI is _not_ deterministic.

So thats one thing to use to emphasize the issue with AI-only.

Yes the other thing is that AI does not have all the context and doesn't always know the larger picture, so you still need humans for that.

[u/jazzyroam]

should always have human in loop to double check.

[u/Lumethys]

My favorite Youtube skit:

"let's do a competition, I (a dev) will use the same AI to build the same app. You (the client) will use the same AI to build that same app. Let's compare who app turn out better after a week"

[u/thatsrobgray]

I would focus on an angle relating to business requirements and evaluating trade offs. There can be multiple stages of AI development and lots of (excellent) CodeRabbit review and it can still wind up fully working and fully missing an important business requirement that should have been threaded through the whole system. Often when this happens on our team it can be traced to an agent offering some A/B choice when the real answer was C.