Over ten years ago, I posed, and answered, The Toilet Paper Question (read it now, if you aren’t familiar with it).
Yesterday, while on vacation, I noticed an interesting design that
implements the solution:
The covered roll has a panel labeled “SLIDE DOOR OVER WHEN EMPTY” and it has a mechanism that makes it difficult to slide when the other roll
Now, there will be an entire roll available for use when an empty one is ready to be replaced; minimizing the chance that they will both be empty before maintenance workers can replace an empty roll.
This is a much better solution than waiting for most people to adopt this reasonable practice themselves.