Of course backup alone is a reason, though I do have a raid-array NAS at home for ultra-redundancy.x9200 wrote:This need of having some TBs allocated in some cloud to be accessible from anything and anywhere... I have problem to imagine why one may want to use it at any practical frequency, or is this just for a backup?
But in terms of "practical frequency"...I would say during my waking hours, at least every 30 minutes is my estimate, for me.
I use OneNote across my PC, tablet, laptop and phone for starters. Any notes, voice clips, web clips, photos or whatever related to my projects is captured in OneNote and instantly available on all my other devices so I can pick up where I left off when I move from phone to PC or tablet to laptop. I use different devices in different situations, sometimes something happens on the fly so I can grab it on my phone and have it there on my desktop when I get back to the office.
If I am travelling with my laptop, anything I do is again, there on my desktop when I get back.
If I am surfing on my tablet on the sofa of an evening and a work email comes in, I can access all my docs without having to boot up the laptop and respond without having to hunt for the latest version.
I can beam my presentation from my tablet to the meeting room projector, edit it based on comments and have the final result waiting on my office PC when I get back.
A photo I take with my phone is instantly available when I sit down at my PC to edit it.
An email I responded to on my desktop is there on my phone when I get a question about it in a meeting.
The video I downloaded and was watching on my TV is there on my tablet when I want to continue watching in bed

I dunno, these are just examples of cross-device cloud integration that I use all the time. I am sure other people have other needs, and there are certainly many services that offer the same features.
For me, I haven't found a sharing/collaboration/storage/backup/cloudsync suite that comes close to the power and versatility of MS Office and OneDrive.