When I was in university (college) I was told a story about a large office building which had notoriously slow elevators. People would often spend several minutes waiting for the elevator to arrive at their floor and the occupants of the building complained about the problem often.
In an effort remedy the problem the owners of the building hired an engineer to come in and recommend ways to speed up the elevator service. The engineer reviewed the existing elevator system and all compatible upgrade options. Eventually the engineer came back with his recommendation:
The most cost effective way to improve the elevator service was to cover the elevator doors with mirrors.
