Nearly 60 Years and Royal Mail Still Can't Get It Right

I recently received the cover shown above. It's a plain white envelope with a single, current Machin and an airmail etiquette. 

Royal Mail's automatic facing and canceling machine had the envelope upside down at the time when the cancel was applied. 

Recently we learned that Royal Mail's equipment will look at the color of the stamp on the envelope and will only apply a full cancel if it finds a valid stamp. How is it that the stamp was identified but the envelope was not faced correctly?

The bar code at the bottom of the envelope was apparently applied correctly. The other barcode, printed in a bright orange color, is more usually under the stamp, if I recall correctly, so I think the envelope was upside down when it was applied.

My name and address were written on a blank label. This is darker under UV than the envelope, and it obviously doesn't phosphoresce.

The British Post Office started experimenting with automatic letter facing in 1957 when the Wilding phosphor-graphite stamps were issued. It's now 2016. How is it that Royal Mail still can't get it right? Perhaps one of our readers knowledgable in postal mechanization can explain this.

--Larry