It's not that hard to host PDF files in the short term, but over the long term you have to do maintenance, and that adds up over time.
For an operation like that you are going need at least one technical FTE, you will be more comfortable with two. (Somebody can go on vacation)
You probably also need one or two FTE for "customer service" functions (e.g. I can't upload file X, I am having trouble downloading file Y)
If you are getting organizations to subscribe to this you also have to run a sales organization, not just to get new customers, but simply to keep getting checks from the customers you have. You need at least one FTE for that, but sales organizations usually develop a hierarchy to the extent that you might have one senior FTE and two junior FTEs.
Then you need somebody to scramble for grants, interface with non-customers, so you get an FTE for administration.
So that gets you to 8 FTE and a wage bill upwards of $500,000 a year. If you had everyone working at full capacity it might be efficient, but if your sales efforts don't get you to full capacity this is a boondoggle.
arXiv.org got started because Paul Ginsparg wasn't concerned about cost recovery at the beginning (no sales), did it as a labor of love, got some people to help him with it as a side project, so it cost at most 2 FTE to run.
Once it got to Cornell it developed a cost structure in line with what I described except the sales and grant-getting functions were neglected so the investment in people to make it sustainable in the beginning still wasn't enough.
I think the best way to understand the numbers would be to look at the breakdown of costs. Two links that were shared from the twitter thread discussing this might be useful:
A few things stand out:
1. Preprints are pretty new. You're not just hosting PDFs on an s3 bucket in maintenance mode- you're also wrangling authors with very different workflows to use your platform. This means building tools for moderation or retraction, and long handholding to recruit 26 partner groups, some of them started as grassroots efforts without their own institutional history. Each group may have their own ideas about governance. (each research field may do things in different ways)
2. In that light, the projected personnel costs are.... not high. The spreadsheet claims that 22% of page traffic going to preprints, but the original 2019 forecast called for ~$7k budget on developers + QA, total. At market rates, that's... a small fraction of the annual cost of a single developer? (their team page lists 10-15 devs on staff)
3. Compared to the overall organizational finances, it suggests that if anything, some of the cost of running the service is being spread across their other offerings. The original vs modified forecasts for 2019 seem a bit, well, different- it's likely that the costs are still being worked out, and may be dependent on hard-to-predict growth.
It's also very notable that this hubbub seems to involve a relatively small amount of cash: the proposed funding model is a 60-40 split, with the service share divided among up to 26 groups. That says a lot about the role of building institutions to support preprints long term, and the need to help grassroots initiatives mature if we want to keep these services active.
https://cos.io/our-products/osf-preprints/
"...this fee structure accounts for $87,976 in contributions by the preprint services toward maintenance costs (38% of total)"
Disclaimer: I don't speak for any of the groups involved in this process, and comments are based only on these public documents. There may well be other numbers or context.
For an operation like that you are going need at least one technical FTE, you will be more comfortable with two. (Somebody can go on vacation)
You probably also need one or two FTE for "customer service" functions (e.g. I can't upload file X, I am having trouble downloading file Y)
If you are getting organizations to subscribe to this you also have to run a sales organization, not just to get new customers, but simply to keep getting checks from the customers you have. You need at least one FTE for that, but sales organizations usually develop a hierarchy to the extent that you might have one senior FTE and two junior FTEs.
Then you need somebody to scramble for grants, interface with non-customers, so you get an FTE for administration.
So that gets you to 8 FTE and a wage bill upwards of $500,000 a year. If you had everyone working at full capacity it might be efficient, but if your sales efforts don't get you to full capacity this is a boondoggle.
arXiv.org got started because Paul Ginsparg wasn't concerned about cost recovery at the beginning (no sales), did it as a labor of love, got some people to help him with it as a side project, so it cost at most 2 FTE to run.
Once it got to Cornell it developed a cost structure in line with what I described except the sales and grant-getting functions were neglected so the investment in people to make it sustainable in the beginning still wasn't enough.