Well it's partly because scammers aren't entirely obvious. Though most have similar shit posts a large majority have taken the time to make the project as convincing as it possibly can be. I remember just last week a coin called EAZY coin had been reported a scam because the developer deleted the discord channel. A month or two before that another coin called ALMEX had it's developer leave for some odd reason even though the project was thriving in terms of trade volume and coin price. Then there was SPARKS coin. The developer also left most likely because of the price drop but a scam is a scam non the less. There is a new community taking that over though, which by the way, are doing a wonderful job of taking it to the next level.