I assume that the comment refers to various jurisdictions that allow the accused to bond out of custody by posting 10% of the bond set and in effect agreeing that a judgment for the remaining 90% would be entered against you for a violation of the terms. The court system typically retains 10% of that cash actually posted.
E.g. $10,000 with 10% applying requires the defendant to post$1,000 cash and agree to pay an additional $9,000 for violating the bond conditions, and the state/county retains $100 as a fee notwithstanding the outcome.
The applicability of the 10% idea is controlled by the statutes of the jurisdiction