For software orgs deploying web services, ”no deployments on Fridays” should be seen as a temporary workaround, not a best practice to follow. It is a symptom of poor automatic QA processes (linting, automatic tests, etc.) and lack of capabilities like feature flags.

The only exception is orgs that need manual QA for regulatory reasons and mobile development, where you follow a weekly/bi-weekly cadence because of external Apple/Google reviews.