I have a lot of valuable digital data. The most precious ones are the photos of my wedding, my kids and all our trips in Japan. I do have all the photos backed up to Google Photos and some to Facebook, but the issues is that neither service preserves original file. Additionally, I have all the 'important' documents backed up to Google Drive.
Locally, I currently have all my data in my DIY NAS. It has currently got two data drives (can support four), which I mirror manually every now and then. While one drive is a backup of the other, the NAS is still a single device. This means, a power surge can kill the server, which can take the drives along with it. And I am not living in Japan anymore. Electricity in Japan was very stable and it only failed once during my 5 and a half year span there. That was on March 10, 2011 when the massive 9.0 scale earthquake hit Fukushima. I think we can excuse that.
I am not saying the power delivery in Australia is unreliable. It is yet to fail since I have arrived here as well, and I've been here for more than 10 months. But Japan runs on Electricity (literally, because of the electric trains), thus it has to be very stable and has to have a lot of fail-safes in place and power headroom. Australia runs on fossil fuel, both literally (i.e. cars and logistics) and figuratively (i.e. power is generated using fossil fuel). Good thing is, the consumption is much less than Japan with 1/7 the population.
Back to my backup plan...