Det er ikke kun fordi at Half-Life-serien var af så høj kvalitet, at fans har ventet febrilsk på et tredje kapitel i årevis - det er også fordi at historien fortsat er uafsluttet og åben. Dog tyder noget på, at selvom Half-Life 3 ville have udkommet, så ville afslutningen stadig have været åben for fortolkning.
Sidste år forlod en af de primære forfattere bag serien, Mark Laidlaw, Valve, og i et efterfølgende interview med Arcade Attack forklarer han et potentielt tredje kapitel ikke ville have lukket historien som fans ville ønske:
"I have no interest in going back. I had ideas for Episode 3. They were all supposed to take the series to a point where I could step away from it and leave it to the next generation. I had hoped for a reset between HL2 and HL3 that was as dramatic as the shift between HL1 and HL2. I honestly don't know if anyone else shared this goal, but it seemed important to me to give ultimate freedom to whoever inherited the series, with my own personal set of loose ends tied up to my satisfaction. Unfortunately, I was not able to do that. But I never thought as far ahead as HL3, unless you were to say that HL3 and Episode 3 were the same thing."
Det lader til at vi aldrig kommer til at finde ud af hvad der skete med karaktererne i universet. Er du ked af at Valve er trådt tilbage fra traditionel spiludvikling?