Here's why:
* "Therefore" is a conjunctive adverb, which means it connects two independent clauses. It's best used to show a logical consequence between the previous sentence and the following sentence within the same paragraph.
* Paragraphs are meant to be separate units of thought. Starting a new paragraph with "therefore" implies a connection to the previous paragraph that might not be clear or intended.
Here are some alternatives:
* Start a new sentence without "therefore." For example: "The evidence is clear. The defendant is guilty."
* Use a transition phrase: "As a result," "Consequently," "Accordingly," etc. For example: "As a result, the defendant is guilty."
* Reword the sentence to avoid "therefore." For example: "The evidence clearly proves the defendant's guilt."
Example:
Incorrect: Therefore, the defendant is guilty.
Correct: The evidence is clear. The defendant is guilty.
Correct: As a result, the defendant is guilty.
Correct: The evidence clearly proves the defendant's guilt.