The passive voice sometimes provides a hiding place for the person responsible.

Mistakes were made is a complete sentence with no one in it. The passive voice has legitimate uses, and it also provides a reliable way to describe an action while omitting the actor, which is exactly why it multiplies in situations where someone would rather not be named.

When you read an account of something going wrong, try rewriting the key sentences with a subject. If you cannot say who did it, that is the missing information. And when you write about your own errors, use the active voice, since I got this wrong lands differently and better than an error occurred.