Vue.js is a popular JavaScript framework that is often used for front-end web development. There are several situations where Vue.js may be a good choice for building the front-end of a web application:

1. Lightweight framework: Vue.js is a relatively lightweight framework, which can make it a good choice for small to medium-sized applications.
2. Progressive framework: Vue.js is a progressive framework, which means that it can be used incrementally, allowing developers to integrate it into existing projects or build new projects from scratch.
3. Reactive data binding: Vue.js uses reactive data binding, which allows changes to the model to automatically update the view and vice versa. This can simplify the development process and improve the user experience.
4. Component-based architecture: Vue.js is built around a component-based architecture, which can make it easy to create reusable UI components and improve the maintainability of the code.
5. Performance: Vue.js is designed to be fast and lightweight, which can improve the performance of the application and enhance the user experience.
6. Developer community: Vue.js has a large and active developer community, which means that there are a lot of resources available for learning and troubleshooting.

In summary, Vue.js is a good choice for frontend web development in situations where a lightweight and progressive framework is desired, reactive data binding is important, a component-based architecture is needed, performance is a priority, or where a large and active developer community is desired.