Digital storage is cheap. Actual storage is...less so...and often flammable.
My application is different than a theater's but is fundamentally similar in that we have active projects, inactive-but-may-be-useful-to-keep-handy projects, and long forgotten projects. Digitally -- all projects, whether active or archived, are organized by project # in folders by calendar year. Active and recently inactive projects are kept
in one volume on the
network storage. Archived projects are on another. The archived volume is read-only for most users. If someone needs to bring a project out of the archives, they contact IT, but mostly what's in there is used only for reference and beyond a certain
point nobody needs to have write access. In my case, each of those project folders include emails, correspondence, contracts,
CAD files, PDF's, project photos, and basically everything related to each project except the HR/accounting/marketing type stuff -- which in terms of write access and workflow rightfully belongs elsewhere.
Having a somewhat standardized folder structure for each active project helps though obviously as organizations evolve, so do their documentation workflows and needs. Going into the archives is often the wild wild west -- pulling project info from 2006 often takes a lot more time because software applications for reading those files have changed and because it wasn't until the early 2010's in my company that everyone got more disciplined in keeping the folder structures better organized.
In terms of analog storage, both at my
current and at my old company there was a tendency to hold onto paper documents
just 'cuz. In both cases, that practice has mostly evaporated. Anything of historical, artistic, or creative significance is scanned and the paper copy may or may not be kept depending on what it is. Everything else was dumpstered. This was of particular importance at my old company because the paper archives were on shelves on a warehouse
mezzanine above the offices. After 20-30 years, the paper archives had grown to a
point where they presented a significant fire and structural hazard. It was time to stop being sentimental and liquidate. During the initial dumpster process, it's perfectly acceptable to hold onto stuff that's a question
mark for another year or so to see if you still think it's valuable to hold onto.
Artistically, it's nice to keep analog copies of representative works or work products that were of significance to the development of the organization. Sometimes that history gets put on display somewhere -- other times it just serves as a milestone marker for people to see how the organization grew and developed over the years. There will be
plenty of run-of-the-mill work products that do not meet that criteria. Also, in terms of artistic work product, if you know the designer involved, it's a nice courtesy to reach out and see if they want to hold onto anything before you toss it. Again though -- for your own sanity apply discretion. Not every piece of paper, sketch, or model is worth the time and effort to do that for. Really depends on what your organization has accumulated.
These days almost everything is digital and TB's of storage cost almost nothing so our overall retention policy is keep everything forever.
I can't talk about storage and not mention than any storage plan should include redundant backups that protect from the possibility of ransomware, malware, hardware failure, employee abuse, theft, accidental overwrites, fire, floods, and tornadoes. Having RAID partitions protects from disk failure but still has significant risk exposure from other areas. At a minimum you should have 3 copies of everything. Maybe the first two are a RAID volume or automated versioning backup of the primary partition, with the 3rd copy being off-site. Remember -- RAID by itself doesn't offer versioning or protection from the growing threat of ransomware. Don't be lulled into a false sense of security thinking that you can get by without the off-site backup, as my former employer did before he accidentally bounced the RAID enclosure off of the back of an equipment rack while pressing the
power button, knocking it onto the floor -- thankfully all that data was recoverable though we suffered some downtime trying to resurrect it.
In the vein of redundancy, there are also some great options like Crashplan and Backblaze that offer relatively inexpensive cloud backups. I gave up Crashplan after I moved to RAID
network drives, but certainly during college it saved my
butt more than once to have file versioning to go back 4-5 versions and resurrect something I overwrote or an idea I discarded that I wanted to take a 2nd look at.