5. Many economists believe that the principle way to ensure a strong economy is to invest in education.
Did you catch all five errors in grammar, punctuation and word choice? Were the subject-verb non-agreement, the comma splice, the nonparallel structure, the missing comma and the misspelled homophone obvious to you?
If not, you may be sending a message of incompetence every time you write. If they were, you likely were so distracted by the errors you had trouble following the meaning of the sentences.
The standard argument challenging the importance of correct grammar runs along these lines: Most people don't notice your errors, even people who do notice don't care, and what does it matter if your grammar isn't perfect as long as your readers understand your meaning? The following assertion takes the argument one step further (not farther) by distinguishing between more significant and less significant errors: Although major errors such as "He don't do nothing right" will exclude you from nearly all professional positions, minor errors don't matter. Again, who cares as long as your meaning is clear?
But people do care, not all people certainly, but many people do, some passionately — people who view proper grammar as a matter of standards and self-pride, people like you and me (not like you and I) whose grammar is good though not perfect and people in authority and key decision-makers like your boss who is annoyed every time you begin a sentence with "me and her," or the human resources manager who is deciding who to interview for a job (or whom to interview, depending on your level of formality), or the college admissions officer who is reading a hundred college application essays before lunch and is looking for an easy reason to stop reading yours.
Errors distract the reader from your message and undermine your credibility even tho they may not interfere with comprehension or peak your readers' curiosity. (Have I piqued your interest?) Even the smallest error such as spelling judgment with an e after the g sends the message "I'm not paying attention" to more sophisticated readers. (In American English the preferred spelling is judgment; in British English judgement is considered correct.)