Your habits teach your conscience what normal looks like.

Your conscience calibrates against your own behaviour. Do something often enough and it stops registering as a choice at all, which is how people end up comfortable with things they would once have refused. The standard drifts quietly, and the drift is invisible from the inside.

Every so often, look at a habit through the eyes of yourself five years ago. Would that person be surprised? Not everything they would flag is wrong, but the surprising ones deserve a proper look.