People do stay, but the ones who stay usually change shape. They stop driving and start systematizing, which means they pull tax-delinquency lists, watch probate filings in their county, run skip tracing to find owner phone numbers, and feed several investors at once. At that point it looks like a small lead-generation business rather than a side hustle. The individual leads still pay a few hundred to a couple thousand on close, so volume is the only thing that makes it a living.
Most people do leave, and the reason is arithmetic. Once you've seen twenty deals get bought, you know what a buy looks like, and the person who put it under contract made a multiple of what you made for finding it. Wholesaling is the next rung and it requires contracts, earnest money, and real exposure if you can't perform.
What you gain in six months, concretely: you learn what price actually clears in your specific area, which is knowledge no course sells you. You learn which sellers are motivated versus merely unhappy. You get three or four investors who take your call, and those relationships are the thing that funds your first real deal, because the person who buys your leads is often the person who partners with you later.
The thing worth guarding is the role itself. Bird dogging stays clear of licensing questions because you pass information and stop. Drifting into negotiating for a seller is where people get into trouble, and the line is drawn differently in every state, so check yours with an attorney before you improvise.