Even when it appears to be running well there are sometimes 'running by the seat of the pants' events that the viewers never see.
A long time ago now, but in the mid 90's I remember a sports magazine programme that went out on a Tuesday evening and was edited right up to the wire, with the transmission tape being laid down (in real time back then) only about an hour before on-air. It was discovered after making the tape that it was unusable due to faulty white-crushed video, and there was no time to remake it as a whole. We ended up going on air with a tape that only had about a minute's worth of good pictures, and within that minute before it ran out we had to sync up and hot-cut to a different tape that had some more pictures, but still not everything, and I seem to remember that we also needed to retain the sound from the original VT as the new tape didn't have that bit, so we now had 2 machines on air running in sync, one with some pictures the other with some sound, but both of which were incomplete. This kind of video/audio hot-cutting had to occur a few more times over the course of the programme as other tapes were still being assembled upstairs and rushed to us to keep things going. And the whole thing had to have the graphics keyed over it live throughout as well. Various edit suites and vision/audio mixers were involved in this feat.
Miraculously the viewer at home saw nothing untoward...
Happy days, and all very different now !