Even though we have only been launching the most basic applications so far, I hope you are starting to see how using serverless could help with the development of your applications.
Imagine you have a JavaScript application which is being hosted in an object store such as Amazon's S3 service. Your application could be written in, say, React (https://facebook.github.io/react/) or Angular (https://angular.io/), and both of these technologies allow you to load external data using JSON. This data can be requested and delivered using a serverless function—combining these technologies allows you to create an application that not only has no single point of failure, but also, when using public cloud offerings, is a true you only pay for what you use application.
As the serverless function is being executed and then is immediately terminated, you should not have to worry about where or how it is executed, just that it is. This means that your application, in theory, should be scalable and also more fault-tolerant than a more traditional server-based application.
For example, if something goes wrong when one of your functions is called, for instance, if it crashes or there are resource issues and you know that when your function is next called it will be being launched afresh, you don't need to worry about your code being executed on a server which is having issues.