You have probably watched Facebook serve you ads for casinos, supplements and things that clearly should not be allowed, on the same day your own perfectly ordinary ad got rejected. That is not you being unlucky and it is not a broken review system. It is a review system working exactly as designed, on signals that have very little to do with how reasonable your ad looks.
Meta is not reviewing your ad in isolation
The single most useful thing to understand is that rejection is rarely about the one creative you just uploaded. Meta scores the account, the page, the domain and the payment method, then reviews the ad against that score. A brand new account with a brand new page pointing at a brand new domain is treated as high risk by default, so a mild claim that would sail through on an established account gets caught.
This is why the casino ad runs. It is not on a new account. It is on an aged account with spend history, a warmed page and a domain that has resolved cleanly for months.
The four things that actually get checked
Account history. Age, total spend, previous rejections and any past policy strikes. A single unappealed rejection on a young account raises the threshold for everything after it.
The landing page, not just the ad. Reviewers follow the link. If the page makes a claim the ad did not, the ad is judged on the page. Mismatched pages are one of the most common causes of a rejection that looks inexplicable from inside Ads Manager.
Personal attributes. This one catches more legitimate advertisers than any other. Copy that implies you know something about the viewer breaks the rule, even when it is positive. "Struggling with your weight?" implies you know their weight. "Tired of being broke?" implies you know their finances. The fix is to move the statement off the reader and onto yourself or the product: "How I lost 20lb" is fine where "Lose 20lb" often is not.
Before and after framing. Any implication of a guaranteed transformation, in copy or in the creative itself, is treated as a claim. Side by side imagery is the fastest way to get a health or finance ad pulled.
What to do when it happens
Always request review, once. The first pass is largely automated. Human review overturns a meaningful share of rejections and costs you nothing. What does cost you is the second habit most people fall into: editing the rejected ad repeatedly and resubmitting. Every resubmission is another rejection against the account if it fails, and you are damaging the account score to save one creative.
Duplicate instead of editing. Build a fresh ad with the offending element removed rather than editing the rejected one in place. Editing a rejected ad puts the whole ad set back through review and can take down deliveries that were already running.
Never make a second account to escape a ban. Meta links accounts by payment method, device, IP and business manager. A new account created to dodge a restriction usually takes the original down with it, and it converts a recoverable situation into a permanent one.
Warming a new account
If you are starting fresh, spend the first two weeks doing nothing that requires a review to go your way. Run traffic or engagement campaigns at a low daily budget with plainly worded creative and no claims at all. You are not buying results in this period, you are buying account history. Then introduce the offer.
It feels like wasted money and it is materially cheaper than losing the account in month three.
The part most people never do
Before writing anything, look at what is already approved and running in your category. Meta publishes every active ad in its Ad Library, searchable by advertiser and by country, with the date each one started running. An ad that has been running for three months is an ad that both passed review and is profitable, because nobody funds a losing creative for a quarter.
That gives you two things at once: proof of what the policy will accept in your category, and a shortlist of angles that are working. It is the single highest return hour in paid social and it is free.