It's maybe hindsight that allows us to know whether the schemes of a huckster are going to fail, but it's not hard to see people who are hucksters. They make big promises and don't meet them, and when that happens they just make another promise (usually including excuses or distractions from why they were previously wrong), and people worship them for that. These people are either liars or just wrong most of the time, but people don't seem to care. It's not that it isn't obvious, it's that people don't want to admit what's right there.
Maybe it is from growing up in an environment where I've seen people who love power and control (even if that's only over a very small amount of people), it desn't shock me that ramps up with increasing power and fame.
There are a lot of people on the scene today which are obvious hucksters, but nobody is going to admit that (and some won't) until their lies actually ruin things. Again, see Draper whom even knowing what he does is willing to lie or be delusional about what happened there.
Consider that there's lots and lots of people who are willing to actually give up their lives for weird cult leaders. If that's the case (and those lies are very obvious to all but a small few), there's so much room on the other side of that where you can be equally as manipulative and fraudulent but because it's only business or politics and not religion, people aren't willing to apply the same standard and say, yeah, that guy is a liar who likes people talking about him (or whatever gender).
Usually people in positions of power have actively sought that power, and it attracts a very specific kind of personality.