Gestation rate on my team's child is eighteen months. The team already knows that eventually, one of the twins will be destroyed by the other in some sort of "In-utero Mortal Kombat" (note for later: this possible could be a fun game idea).
Perhaps games are not conceived when they are published, maybe they are conceived when the concept is presented to the team. Yes, this is more accurate. Our game starts at the conception of an idea, the gestation of the pre-production/idea phase, and the birth is the first playable, the future iterations are adolescence and maturity.
What is the death of a game then? The games of the past are often, "rebooted" and "remixed" and "remade". Some games see no end, like "Minecraft". Some games do die. They die on the shelf, the true death for games and toys are stagnancy, immobility, and the failure to bring joy to people.
