As a writer, I’m interested in the written word. How it connects my mind to yours and how that process goes awry. I’d like to point out something that happens to me quite often on the Internet. I’m reading along, and like an electric shock, some error or other jumps off the page and jolts my noodle. The unseen, jarring pothole throws me off and for awhile I can’t focus on whatever the writer was saying; I can only ’see’ the error.
OK, we all make typos and grammar flubs. That’s not exactly what I mean. What I mean is a sort of usage error that has you publishing, ‘Don’t loose your bowel.’ instead of the intended: ‘Don’t lose your bowl.’
What the psychologists say.
Evolutionary psychology proposes that we are pattern formers because it allowed our predator ancestors to pick out the unusual from the background. And these ‘things that don’t fit’ meant food or danger or ‘go look– be curious’; survival for the guy or gal who could best pick out errors in the pattern.
The point is that the feeling of abrupt interruption is hard-wired in our brains. We can no more turn it off than we can turn off the ‘I think my foot itches’ switch. The significance for writing is that we strive to become invisible to our readers. Unless an article is about me, I shouldn’t appear in it. The dissonance our readers feel when a proofreading error gets onto the page yells out, “Look, someone wrote this– and they goofed.”
The second explanation comes from more general psychology. They point out that what irritates us as individuals most is spotting mistakes in others that we fear to make ourselves. This one is a bit more complex, but has to do with how spotting a mistake makes you feel. If you spot something unconnected to your own ego, or a habit you have yourself that doesn’t bother you, the error will slide past without much emotional content.
On the other hand, if the error is one you would be horrified to make or one you guard against, then you will suddenly, and without will, jump to some harsh judgments about the writer. They will seem uneducated, dumb or careless to you. Readers who experience this (and by the way buyers are also readers) not only loose the flow of the article, but even if they pick it up again, have lost regard for what it says.
I played a little trick on you there. Did the ‘loose’ instead of ‘lose’ throw you off a bit?
My list of common errors.
Here’s a list of errors guaranteed to irritate editors and mark you as a ‘less than educated native speaker’ or worse. The nice thing is having a list largely guards you against them.
Alot/a lot There’s no such word as alot. It’s a lot, two words. Always.
Lose/loose and chose/choose Lose means to no longer have. Loose means ill-fitting or to let go. Chose is the past tense of choose. We choose better today because we chose poorly yesterday.
Affect/effect Affect is verb meaning ‘to cause an effect’. Effect is the noun- ‘Gun control affects how many guns are purchased, and this may have an effect on crime.’ There are specialized uses for both of these: In psychology, affect can be a noun and effect can be used as a verb in phrases like, ‘to effect change’.
Entitle/title The name you use to refer to something is its title. Entitle means a right to ownership. ‘The title of this blog post is Becoming Invisible, as its author, I am entitled to the copyright.’
Its/ it’s Its is possessive. It’s is a contraction of it and is. ‘It’s off-putting when its head has gone missing.’
Loan/lend Lend is the verb. You lend your talent. Loan is the noun. You never, ever loan your talent.
Fewer/ less than Fewer is used with discrete countable things. Less than is used with other quantities. ‘He has less sense than a cow and fewer friends.’
Got a pet peeve of your own? Help me add to my list.

My comment is best written as a haiku:
Become invisible,
Like the writer ninja is,
For great profit! Ha!
One of the most common, thereby most irritating, mistakes would be the verbal use of the word ’supposedly’. How can a person go from the “ed” sound to “sub”?
Supposubly?! Either allow me to puncture my eardrums or rip out their tongues.
…and let’s not forget ‘their’, ‘there’ and ‘they’re’.
I don’t think that the Its/It’s line fully underscores the magnitude of the demonstrated problem. Misplaced apostrophes drive me bonkers! It’s partly because they are so common, and partly because the rule is so simple. Colons and semicolons are tricky. (hehe) I see plurals inappropriately apostrophed in signs, billboards, ads, and other legitimate-looking manifestations of punctuation desecration. How hard can it be!? Excepting the case of the lowly “it,” apostrophes denote possessives or conjunctions.
Spell checkers cannot differentiate between the past and paste. So a proof reading is always mandatory.