React gives you a powerful way to build interfaces, but it leaves routing, rendering, and performance to you. Next.js fills those gaps with proven conventions: every file in the pages/app folder becomes a route, pages are server-rendered for instant loads and crawlable HTML, and static generation plus edge caching keep speed high.
For businesses, Next.js matters because it delivers better Core Web Vitals (a Google ranking factor), stronger technical SEO out of the box, and a much smaller attack surface than platforms like WordPress.