Non-scalable applications hit the business bottom line in two ways : First, application Scalability issues will limit the maximum number of users that can use the application at the same time. Secondly, once that limit is breached, application may become unavailable when the load increases significantly. This may lead to visitors change their mind and switch to an alternative provider. According to Scalability experts, Martin Abbott and Michael Fischer who wrote an excellent small book called, "Scalability Rules," scalability should be designed for in three phases: the design itself, the implementation, and the deployment.
Several years, monolithic architecture has been the widely-used architecture for building the web and mobile applications. These applications were mostly characterized by individual programs handling multiple functionalities. Though monolithic applications were known for easier to operate, as the systems grow bigger, they introduced complexity for both coding and deployment stages of software development life cycle. Single point of failure, technology lock-in, and limited scalability are few other drawbacks of monolithic applications.