I was recently doing the Nurburgring 24hr endurance race B-spec (Audi touring car), when around lap 150 he didn't pit in when he should've. My eyes were bulging, my jaw dropping, but I quite clearly could see the "pit in" instruction still in place. I felt somewhat panicky because his tyres were already wasted, but his fuel situation was dire too. Sure enough, about two thirds of a lap later, just red smudges for tyres, no bars left for fuel.
I thought "That's it, race over, next time pitting every 3 laps regardless" (I'd been doing 3, sometimes 4 laps between pits up till then). However, thankfully, the race was not run or done. A strange icon appeared where you normally see the "crash" icon next to lap time, and he still went on. I went to regular display and he was limited to 80kph but still going, and made it to the pits where he actually went in. Was a long refuel
He was almost 5 laps ahead before this near-disaster, was still 4 laps ahead when he came out.