It was almost "lucky" that this happened when it did. Had they gotten away with the shoddy practices that went into building the Apollo 1 capsule, that fire might have happened in orbit...then Gus, Edward and Roger would have been incinerated in an orbiting tomb... what kind of effect would that have had on the Apollo Programme?
It is however, somewhat dismaying that the lessons of Apollo 1 were not learned later in other programmes. With the Space Shuttle, it was known that there were problems with the O-Rings as early as STS-2, but they flew on, getting away with it for another 22 times until the Challenger disaster in 1986. Then again, it was known that there were problems with the foam insulation on the main tank breaking off and striking the Orbiter during launch, but they flew on until it came back to bit them with Columbia, and another seven astronauts lost their lives.
The key learnings from all these incident is that you cannot simply ignore technical problems; they aren't going to go away by themselves. You might be lucky for a while, but that will NOT last.