I have had one inflight failure due to gearbox self-destruct, chiplight, shutdown and divert in Saudi Arabia. I have witnessed two other failures, one shed most of the turbine through the exhaust leaving some nice dents in those beautiful hand welded parts and another that made it back to base with half of the turbine melted away.

Overall they have proved incredibly reliable though, but like any machine they can and will fail. You can also be struck by lightning. The odds are that neither will happen, but the longer your timeline the more likely a failure.