The 5 steem isn't once. It used to be 2 steem, so the intention is around 1 USD. The timeline hasnt started counting, so some have been certified for many months already on the same payment. Also, not every certified user made a payment. The payment is mostly a hurdle and there is a lot to being certified. Ultimately, being certified has to do with being true fans. The payment, incentive or the perks, those things are secondary. There are 4 steps to getting certified. You will find these steps here: https://www.marlians.com/@surpassinggoogle/simplified-process-for-becoming-a-certified-ulogger-now-4-very-simple-steps-only-chinese-and-korean-translation-available

Being certified is also optional.