it depends on what your remotes are, and what your risk profile is. consider the problem that your internet access may go down and you are cut off from all your backups, unless one of those is your parents house where you can get to without internet.
I touch my backups less than once a month and I lose internet less than once a month so I think I'd just shrug if those overlapped and I didn't have local backups.
depends on where you host your data. a decent provider will include a few terabytes of traffic per month. and since you won't have a lot of people accessing that data, your traffic won't exceed that of a moderately popular website.
But that's my point, to answer the question asked. You're mirroring between two cloud providers, one cuts you off and you need to egress all your data ASAP from that provider, to a new one. If you have your primary local, you just push to the new provider free.
Example: my work places all our files, including your docs and desktop folder, on OneDrive. There is a local cache, but they don't actually let you do a full sync to local to minimize egress
Example: they replaced my laptop, I had about a TB of data generated on the old one. It's all in OneDrive. I power up the new laptop. I can't just sync everything to it - they disable that via policy. Every time I open something for the first time, it downloads. So if I wanted to say, copy all my crap to AWS. Now I have to Egress the whole thing from Azure.
Now, imagine you have more than a TB. Not arguing either way - just answering the question.
sure, i understand that. but it suggests that OneDrive may be convenient but ends up being expensive for lots of data. i have a root server, which means more work to set up, but i get 10TB traffic per month included in the hosting price. i am more likely to get in trouble with my local ISP if i download more than 1TB than with my hosting provider.
anyways, we obviously both agree that having a local copy is a good idea either way, and i appreciate your additional examples of the problems that one can run into with a remote only backup
I don’t see how that is better than two or three remote backups?
Do I need to change my strategy?