So, I'm with Santara on this one but that's b/c I'm a political nerd. A caucus seems REALLY fun and it's a great way to discuss politics with your community. It's also reasonably close to ranked choice voting so that's an added benefit. I personally think that primaries should be closed (only party members can vote) but that's another topic of discussion.
I know that some people just want to have primaries on a single day, but if you had that, you basically give the nomination to Clinton, Biden, Jeb, etc. every single time. Honestly, this isn't really a problem with the Iowa caucus, it's just with reporting information. If it was a primary, you'd still have issues b/c each precinct needs to report their results. Granted, it'd be easier to report the results, but you'd still have a delay due to technology failing.
Nate Silver is pretty annoyed that his model got screwed:
https://fivethirtyeight.com/features/iowa-might-have-screwed-up-the-whole-nomination-process/Honestly, it seems like the person who got screwed the most in this is Mayor Pete. If he really did get the most delegates in Iowa, that's a Cinderella story that got overshadowed by this colossal fuck up. Imagine what would have happened if the news of Obama's Iowa win didn't make it until 18 hours later.