When George Bernard Dantzig was late for his class at the University of California in 1939, he copied down two Math problems on the blackboard that he thought was the Math assignment to be completed.
He tried to solve the two Math problems with great difficulty and he took days to solve them.
He eventually completed them and submitted to his professor.
He waited anxiously for his grades after many days until he was called into the Dean Office one day.
There were many people in the office waiting for him and he thought he was trouble.
He eventually found out that he had solved two unsolvable Math problems.
His solution had shocked everyone since even great minds were not able to solve them down the years after many attempts.
It was indeed an accidental achievement for him.