You missed a couple of threads asking for longer timers:
Also, there have been calls for longer timers in individual posts on several other threads, but I’m too lazy to dig for that.
Yeah, because they made absolutely no announcement when they did so. Instead, they announced it 7 days after the change.
To put things into perspective, they used to adjust the timers only during summer time (for the Northern Hemisphere at least), so people could go on vacation without worrying about decay, and they would always adjust it back to normal afterwards. So it was fairly predictable, and people didn’t risk losing their builds unknowingly.
They broke with this tradition by leaving the “summer decay timers” on official servers “until further notice”, which wasn’t a bad thing per se, but it made it impossible for people to predict when decay timers would go back to normal and plan accordingly. What was a bad thing was to follow up with an unannounced change to normal, which caught some people with their metaphorical pants down, so they lost some of their stuff.
I hope that’s enough context for that particular bit of history 
As for why they did this, my personal guess is because they know that some people can normally only play on weekends, and they don’t want those people to be affected by another weekend outage. For that matter, it seems like the problems that caused the last outage still haven’t been completely fixed.