Is it neccessary to use Three Tiered Architecture in ASP.Net Websites and Web Applications

Architecture is mainly as the name suggest for Architect of the Application.

# Tier Architecture allows you to easily have common classes, methods and also make changes without disturbing application layer.

#Also it simplifies the application for future changes due to less code

#The same DataLayer and Business Layer can be shared across multiple apps

 Professionally anyone must use Tiered Architecture for long run