What's the hardest part of troubleshooting automations?

Hey everyone! :)

I've been speaking with people who build automations and integrations about how they troubleshoot when something isn't working and the cause isn't obvious.

A lot of it seems to involve checking executions, comparing data, testing different things and trying to narrow down what's actually wrong.

I'm curious, what's usually the most frustrating part of that process for you?