The description is quite accurate. It simply means that the camera will focus the lens at infinity each time it is powered on. Many modern lenses can focus beyond infinity and have no stops at infinity, so when shooting very distant subjects such as stars it is difficult to focus, particularly since light is very low.
While I almost always turn off that feature, it could be useful because depth-of-field is relatively deep at infinity. So while you may not be have to get the maximum focus-depth as you suggest, you can easily frame your shot. Should the lens have been close to its near limit, the preview is highly lke to be quite blurry.
Keep in mind that if you have severed the electronic link to the focusing element, this feature does nothing, For examole the M.Zuiko 12mm F/2 allows the focus-ring to slide back toward the mount. In that position, the camera cannot change the focus distance at all.