The performance existed beyond any one playthrough
Commander Shepard’s dialogue in Mass Effect was built for a story that could branch according to player choices. That means the recorded performance had to cover more than the lines a single player would hear: different responses, reactions, and paths through a conversation could all be part of the game’s voice track.
A finished playthrough, by contrast, follows only one route through those possibilities. Hearing the complete performance would require encountering lines that many players never select—and choices that may lead to different scenes altogether.
Recording dialogue is not the same as playing the story
A voice actor can work from scripts and recording sessions without experiencing the game as a player does. The work centers on delivering the assigned lines, with enough consistency for Shepard to sound like the same character across scenes and story branches. The game’s software later connects those recordings to the player’s choices.
That separation helps explain how Mark Meer could voice Shepard across an enormous amount of branching dialogue while saying he did not really play the finished games himself. The recorded character contains many possible Shepards; each player meets only the one their decisions bring forward.
