Mission planning in 5th gen warfare is a matter of information warfare. Knowing the number of ground radars and aerial threats is crucial. Given this, the software can either compute a trajectory, in which case the mission is a go, or fail to produce a result. As in anything, no plan is flawless and there is a chance of detection, in which case you engage. There is no such thing as 100% invisibility, but 5th gen tactics give you an increased survivability and mission success. Also, how you use this also matters. There is no substitute for cunning and deception.