You have finally finished writing your article. You’ve sweat over your choice of words and agonized about the best way to arrange them to effectively get your point across. You comb for errors, and by the time you publish you are absolutely certain that not a single typo survived. But, the first thing your readers notice isn’t your carefully crafted message, it’s the misspelled word in the fourth sentence.
It is infuriating. There is also the Law of Conservation of Typographical Errors. This applies to long works such as books. It states that for every typographical error you correct, another one spawns in the book. I’ve seen it happen.
When you’re proof reading, you are trying to trick your brain into pretending that it’s reading the thing for the first time. Stafford suggests that if you want to catch your own errors, you should try to make your work as unfamiliar as possible. Change the font or background color, or print it out and edit by hand. “Once you’ve learned something in a particular way, it’s hard to see the details without changing the visual form,” he said.
Indeed. When you do that, you see it in a different light. I often use a different font to proofread what I’ve written on my computer. But their are still typos anyway.
Source: What’s Up With That: Why It’s So Hard to Catch Your Own Typos | WIRED