RE: The number 1 reason to join Hive

This is a complex question. Joining Hive remains a significant challenge. I would definitely offer my friends who are interested in Hive everything I know about it.
However, if I were to do it intentionally, I would profile those interested. For example, photographers are an interesting profile to join Hive, as there are many photography-related contests offering rewards.
Then, all those who are involved in finance and crypto, on HE, you have hundreds of tokens with which you can buy and sell in all possible ways, here you can learn tokenomics, then various interest communities, not least owners of small businesses who can easily integrate HBD and BTC payments (of course, depending on the legislation in the country). But I would not invite anyone with the intention of easy earnings here, because that is not the case.