You could increase the startup time and decrease performance of your applications if you create too many objects or put too many objects into a single view. To improve startup time, minimize the number of objects that are created when the application is first loaded. If a user-interface component is not initially visible at startup, avoid creating that component until you need it. This is called deferred creation. Containers that have multiple views, such as an Accordion container, provide built-in support for this behavior. You can use ActionScript to customize the creation order of multiple-view containers or defer the creation of other containers and controls.

After you improve the actual startup time of your application as much as possible, you can improve perceived startup time by ordering the creation of containers in the initial view. The default behavior of Flex is to create all containers and their children in the initial view, and then display everything at one time. The user will not be able to interact with the application or see meaningful data until all the containers and their children are created. In some cases, you can improve the user's initial experience by displaying the components in one container before creating the components in the next container. This process is called ordered creation.

The remaining sections of this topic describe how to use deferred creation to reduce overall application startup time and ordered creation to make the initial startup time appear as short as possible to the user. But before you can fully understand ordered creation and deferred creation, you must also understand the differences between single-view and multiple-view containers, the order of events in a component's startup life cycle, and how to manually instantiate controls from their child descriptors.