If costs matter to you, e.g. for home backups, don't buy Glacier (and heck don't buy S3). A 3TB drive costs about 110eur, so if you'd have to buy a new one every year (you don't) that'd cost 110/3/1000/12=0.31 cents per gigabyte per month. Glacier? 7 times more expensive at 2.3ct.
Hardware is usually not a business' main cost but it does matter for home users, small businesses or startups that didn't get funded yet, some of whom might consider Tarsnap or some other online storage solution which uses Glacier at best and S3 at worst. Now you could suddenly be 7× cheaper off if you do upkeep yourself (read: buy a raspberry pi) and if you throw away drives after one year.
There is value to having off-premises replicated storage on something more durable than home-user targeted drives.
Google cloud nearline costs $0.12 per gigabyte-year with prices that will continue to fall. For a typical 500g hard drive that saw perhaps 700g of unique data, that's $84/year to have an outside-the-house replicated backup using something like Arq.
They are not the same thing at all. Glacier is the backup of the backup. It's where you go if your house burns down and the offsite backup at a relatives house is destroyed as well.
If you want to compare them, you have to buy space on a different continent, and store your backup there.
> A 3TB drive costs about 110eur, so if you'd have to buy a new one every year (you don't) that'd cost 110/3/1000/12=0.31 cents per gigabyte per month. Glacier? 7 times more expensive at 2.3ct.
Your pricing assumes that the drive is never powered.
I had such a setup when the Joplin 2011 tornado hit: http://www.ancell-ent.com/1715_Rex_Ave_127B_Joplin/images/ and I got off lightly. But the separate room my BackupPC hard drives were in was breached (see 302-2nd-bathroom-with-hole-of-unknown-origin) and those drives become fit only for Ontrack's $$$ recovery service, maybe, and one of my computers with e.g. my email was seriously damaged. The data on it was easily recovered from rsync.net's off site Denver location, who's service I love and will continue to use for my most important and "hot" data.
LTO (-4) tape had gotten capacious and cheap enough that I went back to tape (I'd outgrown DAT); if I didn't have a big sunk cost in a well working tape system and pool of tapes, which are very easy to put in e.g. a safe deposit box (they're a bit fragile, but nothing like a hard drive), I'd already be using one of S3, Glacier, or Backblaze, maybe even GCS since suddenly and irretrievably losing access to my backup data because a bot decided I was evil would not likely coincide with a total data loss at home (Google simply cannot be trusted if you're small fry like myself, as HN has been discussing as of late).
As Glacier has gotten sane enough to use without twisting your mind into a pretzel, with the new price reduction for slow retrieval I can seriously think about adding it to the mix and switching to it when my LTO-4 tape drive dies someday (e.g. ~3TiB for ~$12/month per my quick calculation just now), instead of buying another tape drive.
Hardware is usually not a business' main cost but it does matter for home users, small businesses or startups that didn't get funded yet, some of whom might consider Tarsnap or some other online storage solution which uses Glacier at best and S3 at worst. Now you could suddenly be 7× cheaper off if you do upkeep yourself (read: buy a raspberry pi) and if you throw away drives after one year.