Since users can open as many programs as they like, this is a potential cause of performance problems. In addition, since the WPS will restart any programs which were left running at "shutdown", we can conceive of a situation where performance would slowly degenerate over some time, with the operating system starting more and more programs each day, even if the user didn't need them all.
There are two techniques which can help prevent these problems. The first one is to use work areas instead of folders, then encourage users to close a folder when they have finished with it instead of minimizing it. When a work area is closed, all the programs in it are also closed, so this helps free resources for the next program(s) the user has to run.
The second technique is described in Prevent Programs Restarting at IPL, where any previously running programs are prevented from restarting when the system is restarted. A REXX program is described which performs this.
In addition, some WPS functions are inherently slower than others. For example, opening a folder with a tree view is slower than opening it with an icon view. Users quickly learn to use the WPS functions in the most appropriate way.