[FullMtlAlcoholc]

"There wasn't much thought put into how it was supposed to play, but Epic 100% did not see where this was going, nor did the community at the time. And that was very much instrumental to it's success. Had Epic saw this coming, they would have totally destroyed the mechanics that made it so good right off the rip."

Similarly, combos in fighting games were originally a bug. In the original Street Fighter 2, you could attack someone two or three times before they could block or counterattack (I believe the initial term was called a 2 in 1). Capcom liked what it did to the game, and consequently kept it in.