Also predictability, resilience, sovereignty. I'm not worried about other people's outages, that unexpected demand will impact me at an inconvenient time, that someone's watering down my model, that my costs will change unpredictably or that some unforseen error will lead to a huge bill.

It's in the same category as rooftop solar for me. It doesn't have to make strict economic sense if you're the particular type of person who gets peace of mind from control of infrastructure / reduced dependency.