The obligation to preserve relevant material arises when litigation is reasonably anticipated, which is usually well before a complaint is filed.
At that point automatic deletion policies, mailbox cleanups and device wipes have to be suspended for anyone likely to hold relevant material. A litigation hold is how that is documented.
Failure here creates a problem independent of the underlying claim. Sanctions can include adverse inference instructions, which is a jury being told to assume the missing material was unhelpful to you.
