Nextjs Guideline: Rendering — Use streaming for better UX. Description: Stream content with Suspense boundaries. Do: Suspense for slow data fetches. Don't: Wait for all data before render. Good Example: <Suspense><SlowComponent/></Suspense>. Bad Example: await allData then render. Severity: Medium. Docs: https://nextjs.org/docs/app/building-your-application/routing/loading-ui-and-streaming.