Have you ever had to defend your decisions and proposals to colleagues during a project?

Yes, such situations have occurred. For example, when choosing an architectural solution or a library for a project, I sometimes had to justify my choice to the team. In such cases, I would highlight specific advantages of the chosen approach, considering the project requirements, performance, community support, and ease of integration. It is also important to listen to colleagues' feedback and be prepared to make compromises if their arguments are convincing.