Everybody involved in creating large documents has most probably encountered it, the Selfsumi, or the ‘Self Sustaining Mistake’.
There, it finally has a name.
But how come we keep on making these mistakes?
After you type something, your brain will run sort of an automatic background spell check. Once things pass this spell check, either by being correct, or just because you where temporarily distracted, your brain is less inclined to check it again. This is how a Selfsumi is born.
It passes our mental “security barrier”, after which a piece of a sentence becomes invisible. This mistake is then easily copied and pasted throughout several files or pages.
Since copy-pasting is second nature to anyone using a computer, the spread of a Selfsumi can take on an almost viral scale.
Sometimes a Selfsumi can even cross the barrier between multiple files and even people.
Now Selfsumi’s are mostly harmless. Until they are not. Often copy-pasting information throughout several texts is what makes a text “go bad”. This is something I like to call File-rot, or in the case of a PowerPoint file, Deck-rot (which is where I encounter most of these). Deck-rot will manifest itself in random crashes, the inability to export, or even as far as a corrupted file that will not open anymore.
I can’t give any advice to prevent these things from happening. Next time when you copy-paste something, look at the result, and don’t just leave it for what it is. At least now the beast has a name.