I know of a very experienced reloader and competition shooter that loaded a .308 case with 40.5 gr of WW231 thinking it was WW748. The first round of that he fired in a M1A, the gun came apart and he was slightly injured. That taught me a good lesson about having more that one type of powder on the bench at any time.
And just like that...
Everyone who loads or is interested in the practice should take note. I was blessed with family who taught me one on one and I picked up their good habits. Still had to learn a few lessons on my own and still have all my fingers and both eyes, lol.
Good post.