In a milestone, you may want to combine several conditions together.

For stories and articles, you will typically select a workstate, and fitting condition. For  images, you will typically select a workstate, not dummy condition.

For pages, you may want to combine a workstate and printing status. Use workstate if a page is to be approved manually. Avoid to use workstate, if you want the page gets closed automatically as soon it is sent to a type setter.