The Challenger disaster is on the list but should be expanded upon:
1) Considerable pressure from NASA to cover up the true sequence of events. They pushed the go button even when the engineers said no. And they failed to even tell Morton-Thiokol about the actual temperatures. NASA dismissed the observed temperatures as defective--never mind that in "correcting" them so the temperature at the failed joint was as expected meant that now a bunch of other measurements are above ambient. (The offending joint was being cooled by boiloff from the LOX tank that under the weather conditions at the time ended up cooling that part of the booster.)
2) Then they doubled down on the error with Columbia. They had multiple cases of tile damage from the ET insulating foam. They fixed the piece of foam that caused a near-disaster--but didn't fix the rest because it had never damaged the orbiter.
1) Considerable pressure from NASA to cover up the true sequence of events. They pushed the go button even when the engineers said no. And they failed to even tell Morton-Thiokol about the actual temperatures. NASA dismissed the observed temperatures as defective--never mind that in "correcting" them so the temperature at the failed joint was as expected meant that now a bunch of other measurements are above ambient. (The offending joint was being cooled by boiloff from the LOX tank that under the weather conditions at the time ended up cooling that part of the booster.)
2) Then they doubled down on the error with Columbia. They had multiple cases of tile damage from the ET insulating foam. They fixed the piece of foam that caused a near-disaster--but didn't fix the rest because it had never damaged the orbiter.
Very much a culture of painting over the rust.