Took me at least a half dozen attempts tp complete Hold for Reinforcements Elite at level solo-with-Cleric-hire back in the day, and I've wiped as part of a full group during In The Flesh Elite at level on more than one occasion.
I've also failed The Cannith Crystal multiple times in a row when trying it Elite with no hire pre-Champions - often quite literally to a single hit crit destroying the crystal (you get a slightly different fail message when this happens). I have seen this happen on multiple occasions.
When playing Nethack it could quite easily take me 20 attempts to complete the game. But then again, that's actually a quite hard game.
Point is not my rubbishness at the game, but instead that if I can complete it with a no weapons no items first life Rogue, it is not impossible for newcomers to do the same. it just needs a bit of thought and - shock, horror - tactics.