I learned this the hard way when I tried to turn our attic into a guest room last year. I got so caught up in the insulation hype that I barely thought about airflow. Ended up with a space that felt like a sauna in summer and weirdly damp in spring. Had to go back and add vents after the fact, which was a pain. If I could do it over, I'd definitely focus more on balancing insulation with proper ventilation from the start. It's not just about cramming in as much insulation as possible... sometimes you really do need to let the place breathe.
Totally get where you’re coming from—people always talk up insulation like it’s the magic fix, but if you skip ventilation, you’re just trapping problems inside. I’ve seen folks go all-in on spray foam and end up with moldy corners or crazy temperature swings. Honestly, I think a lot of the “hassle” comes from not planning for both comfort and air quality. If you’re gonna convert a space, it’s worth mapping out airflow from the start, even if it means spending a bit more upfront. Otherwise, you’re just setting yourself up for headaches down the line.