Why small groups beat private lessons (for most people)

Private lessons have one conversation partner: a teacher who understands your mistakes, adapts to your accent, and never gets impatient. That's exactly the problem. The real world doesn't adapt. A group gives you five other accents, five other speeds, five people who will ask you unexpected questions.

There's also the observation effect: you learn from errors you never make yourself. When a classmate confuses 'since' and 'for' and gets corrected, that correction lodges in your memory without costing you anything.

Groups also solve the motivation problem that quietly kills most private arrangements. A standing appointment with seven people who noticed you were absent is a stronger commitment device than an appointment you can reschedule with one text message.

We cap conversation groups at eight — beyond that, individual speaking time collapses. At six to eight, you get the best of both: enough voices to be unpredictable, few enough that everyone speaks in every class.