docs: add "Why Choose Vaadin?" article

articles/building-apps/why-vaadin.adoc

@@ -0,0 +1,66 @@
+---
+title: Why Choose Vaadin?
+page-title: Why Choose Vaadin for Web Apps - Vaadin Docs
+description: Understand what makes Vaadin a good fit for business web applications.
+meta-description: Learn when and why Vaadin is a strong choice for building data-heavy business web applications with Java, Spring Boot, and web components.
+order: 1
+section-nav: badge-deep-dive
+---
+
+
+= Why Choose Vaadin? [badge-deep-dive]#Deep Dive#
+
+Vaadin is an open-source Java framework for building web applications. It runs on Spring Boot, Jakarta EE, or Quarkus. Vaadin is designed for internal business applications, admin tools, and data-heavy UIs where developer productivity and security matter more than pixel-perfect consumer design. This article explains what Vaadin does well and where it may not be the best fit.
+
+
+== Full-Stack Java Development
+
+Vaadin Flow lets developers build web UIs in Java without writing JavaScript, HTML, or CSS. The UI runs as Java objects on the server, and Vaadin handles client-server communication automatically. This means Java developers can own features end-to-end, from the database to the UI, without context-switching between languages or frameworks.
+
+Teams with Swing or JavaFX backgrounds find the programming model familiar: create components, add listeners, and update state in plain Java. There is no REST API layer to design and maintain between the frontend and backend. The full Java ecosystem — libraries, tooling, type safety — is available directly in UI code.
+
+See <</building-apps/ui-basics#,UI Basics>> for details on the server-side programming model.
+
+
+== Ready-Made Components for Business Apps
+
+Vaadin provides 40+ UI components designed for data-heavy applications. <<{articles}/components/grid#,Grid>> handles large datasets with lazy loading, sorting, filtering, and inline editing. <<{articles}/components/form-layout#,Form Layout>> and the <<{articles}/components/text-field#,input components>> support data binding with built-in validation, reducing boilerplate code for common CRUD operations.
+
+All components meet WCAG 2.1 AA accessibility standards. They are built on W3C Web Components, making them interoperable with standard web technologies. A consistent visual design system ties the components together, so applications look professional without custom styling effort.
+
+Browse the full <</components#,component catalog>> to see what is available.
+
+
+== Security by Default
+
+Server-side execution keeps business logic and data-access code out of the browser. Users cannot inspect or tamper with application logic through browser developer tools. Vaadin provides built-in XSS protection through automatic input sanitization and manages the client-server communication layer to prevent common web vulnerabilities.
+
+Vaadin integrates with Spring Security for authentication and authorization. Because there is no public REST API surface by default, the attack surface is smaller than in typical SPA + REST architectures.
+
+See the <</building-apps/security#,security guides>> for implementation details.
+
+
+== When Vaadin Is a Good Fit
+
+Vaadin works best in specific contexts:
+
+- **Internal business applications**, admin panels, and back-office tools where developer productivity outweighs custom visual design.
+- **Teams with Java expertise** that want to stay in one language across the full stack.
+- **Data-heavy applications** with complex forms, tables, dashboards, and workflows.
+- **Projects where security and time-to-market** matter more than fine-grained frontend control.
+- **Spring Boot or Jakarta EE projects** that benefit from tight framework integration.
+
+
+== When to Consider Alternatives
+
+Vaadin is not the best fit for every project:
+
+- **Public-facing consumer websites** that depend on search engine indexing benefit from server-rendered HTML or static site generators.
+- **Offline-first applications** require client-side state management that conflicts with Vaadin's server-side model.
+- **Teams that prefer JavaScript or TypeScript** on the frontend may find the server-driven approach limiting.
+- **Highly custom visual designs** that diverge from the component library conventions require more effort to implement.
+
+Choosing a framework involves trade-offs. The points above help identify whether Vaadin's strengths align with the project's requirements.
+
+[TIP]
+The <</getting-started#,Getting Started>> guide walks through creating and running a Vaadin project in minutes. Try it before committing to a framework decision.