Honestly, that "test of patience" part is exactly what makes it so hard. It's not the complexity that gets you, it's the sheer frustration of something simple taking forever.
Oh man, I have to disagree a little. It's not that it's hard, it's just super tedious. Like, following a recipe that has twenty steps when you just want to eat. Or untangling a necklace chain for an hour. It's not difficult skill, it's a test of patience.