Judicious use of repetition can be a very effective rhetorical device, especially in written and oral advocacy. Judicious use, mind you.
Winston Churchill made memorable use of repetition: We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills.
Lawyerly writing, on the other hand, tends to repeat things because the writer doesn’t want to allow an iota of uncertainty by substituting a pronoun like it or that, or a synonym – or because the writer hasn’t taken the time to edit.
Ask yourself, for example, whether you really need to repeat a defined term ad nauseam. You may in contractual drafting, for the sake of certainty, but in a case comment or client update the context may make things clear without dull duplication. If you’re careful, it or that can work just fine.
If you read your piece aloud, you will be more likely to spot the kind of repetition that makes your prose leaden rather than lively.