> If we lowered the expiration time to say 3 days, with automatic renewal after 2 days, then any breakage on your side or downtime on let's encrypt's side would

> If we lowered the expiration time to say 3 days, with automatic renewal after 2 days, then any breakage on your side or downtime on let's encrypt's side would quickly escalate into https errors. That in turn would train users that those just happen, and make them ignore the big red scary page even when it's an actual attack. That sounds much worse than the small risk from a 30 day certificate. That's already happened. I'm encountering LE errors on random websites so much that I don't care and automatically click through warnings. This is especially troublesome because my government keeps MITM me and I don't like it.