Many products on the Android Market which include task management functionality support a feature known as "automatic task killing". Such programs will automatically kill running tasks at regular intervals, typically on the premise of extending battery life or saving memory.
The problem with automatic task killing is that it does not provide any benefit.
As previously discussed in the Task Mangement Section, the Android operating system knows how to manage memory. It automatically loads processes into memory and unloads them as required. Android will strive to always use as much of your device's memory as possible, and this is a good thing: empty memory is wasted memory. Do not be concerned if your device does not show much memory available. If the application you are using requires more memory, other (background) applications will automatically be removed from memory.
Non-running applications which are residing in memory also don't use any battery power. It takes the same amount of power to store "nothing" in memory as it does to store "something" in memory. It does however take power to periodically kill running applications. It also takes power for the operating system to react to a condition where very little memory is in use and attempt to preload new applications into it (Android isn't expecting sudden large increases in the amount of free memory).
There is a case where automatic task killing does actually work. If you have a badly designed application that runs in the background and needlessly consumes CPU, automatic task killing will likely end it and cause Android to preload some other application instead. Chances are the other app won't be as poorly written and will consume fewer resources, thus extending battery life. SystemPanel solves this problem with the monitoring service, which allows you to see what applications are consuming excess resources, and then either uninstall them or report the undesired behavior to their developers such that they may correct them.
Manually using the "End All" feature of SystemPanel to emulate automatic task killing is an equally bad idea. The "End All" feature is best used if you're having trouble with your device and are uncertain of the cause.