Excellent questions. Perhaps it depends on the nature of the expected failure - I'm not sure what it was. Could be that it could start a fire, explode, spew oil all over the track, or maybe simply shut off. Was worth it for the win though, I think ... though I also expect they were not intending to salvage the PU. Half the grid had new engines this weekend, and I think they're allowed what ... 4 for the year? I think RB were going to replace it after this race.