Really fast feedback is great

Feedback is great, fast feedback is better, and really fast feedback is disproportionately effective. Really fast feedback is so effective that it's often worth sacrificing on other dimensions (including, but not limited to, p50 response time) to give more feedback quickly. By "effective" I mean effective on any relevant dimension: education, persuasion, deterrence, amusement, or whatever else. Obviously I can't prove this in general, but: I have abundant anecodotal evidence of this, both in giving and in receiving really fast feedback, in education and other domains. Patrick McKenzie says so: he jokes that he has a policy of paying contractors "net 30," but the "30" means 30 minutes. Researchers tell us (e.g., here) that not just the certainty but the speed of punishment is important to its deterrent effect.1 It's a principle of software design: it matters a lot how quickly you tell the user the most important information. It's a principle of dog training: a lot of communication is…