Grammar Matters
People are often surprised by what constituted a "classical" education. Education in ancient Rome was heavily focused on grammar. Why? Because the highest aspiration of an educated Roman was to make convincing arguments to get his (sorry ladies, the ancient Romans weren't into gender equality) clients off the hook for whatever crimes they were accused of perpetrating (much like the decisions of the legal system here in the modern United States, the decisions of Rome's legal system were more dependent on the ability of lawyers to spin a good yarn than what the evidence indicated).
A brief conversation with the average person will quickly prove that modern education isn't terribly concerned with grammar. But I urge people to study grammar. While the highest aspiration of an educated person today may not be to impress a judge or jury with impeccable storytelling, the proper use of grammar can still pay dividends:
A pair of student drug dealers have been spared jail after a judge was impressed by the 'spelling and grammar' of the texts they sent advertising their product.
[...]
A court heard police examined their mobile phones to find text messages relating to their drug deals composed using perfect spelling and punctuation.
Judge David Hale said the 'grammar and punctuation' in the messages was of a much higher standard than normally seen from dealers and indicated a higher level of education.
The bar is set sufficiently low that the appropriate use of a single comma or period qualifies as a "much higher standard than normally seen." But that's good news for anybody who "don't write so good." They don't have to study for long to become better than average.