Guerrilla Testing

Fast, informal usability testing conducted with whoever is available, friends, coffee shop strangers, conference attendees, rather than recruited participants. Fast, cheap, and surprisingly effective.

In games, this means

Sitting in a café with a laptop and asking strangers to play your game's first 10 minutes while you observe silently costs nothing and can surface critical onboarding failures in an afternoon. It lacks the rigour of formal testing, self-selection bias, non-representative participants, no controlled environment, but for early builds it is dramatically better than no testing at all. The rule: five strangers is enough to find your biggest problems.