They do, but sometimes they wait until the second round.
You will get limited. If not sooner, then soon enough. It's part of the program they run.
It's based on volume, velocity, specific item, every facet of money transfers, and so many other things. There is no single definite answer. It will be different for each person.
Some people get their first listing killed. Some people list a 100 and then get slammed.
The slower you start and more gradually you grow, the long you are likely to last. At some point you will get limited and they will ask you for papers. Might be invoices of suppliers. Might be your driver license. Might be a copy of your most recent bank statement. You can't avoid it at some point.
You can find a few hundred more answers to this very question by searching '21 day hold' at the top of the page. It's been asked by the vast majority of people here, often within 90 seconds of logging in the first time. I'm not trying to come across as rude. I'm trying to steer you toward what has already been said many times over.
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