A good read to compliment what you saw in the video can be seen by going here:
Also thing that I see a lot of when doing security assessments in archive storage areas, are cabinets like the ones I have attached to this post. On many occasions I have noted keys in the locks of the cabinets, or just lying on top of the cabinets.
A common misconception is that since archive storage is in a locked room with alarms it’s okay to leave cabinets unlocked, or keys left in the locks. Having locking devices on cabinets containing archival/collection items is one way we protect these items. However when we leave the keys out, like in the example pictures that I attached, it increases the chance of theft. .
We want it to make it harder for a thief to steal, whether it is from an insider or an outsider, so good key control policies, procedures and practices are a crucial part of the process.