All new CS2 items are put on Auctions in the first 24 hours - when they still have 8 days trade-lock.
The auction system is simple and works like this:
First item price is 120% of current item price
Every 6 hours it is reduced by 5% - to 115%, 110%, 105%, 100%
Users have chance to reserve such item, the next price is always displayed over the item