According to the Co-creator of Left 4 Dead, Chet Faliszek. The original two conceived titles for Left 4 Dead were: "Terror Terror Terror!" And "Blood Run".

"Terror Terror Terror!" had briefly been trademarked before being dropped as a title, but "Blood Run" was rejected promptly due to Faliszek hating the word 'Blood' being in it.

Eventually after a list of titles were suggested, Erik Wolpaw was the one to come up with "Left 4 Dead".