Point me to a man who isn't a coward in some area of his life and I show you a liar or a self-deluded. But maybe valhalla has no problems with admitting the liars and the deluded. Doesn't sound like much fun to me though. Maybe that explains the necessity for all that beer.
remember social context, they believed being a warrior was of the highest order, so being a lier or deluded has no bearing on it, you wouldn't find it much fun, unless you like eating, drinking and fighting to the "death" (being dead already has its perks), then doing it all over again till the midgard serpent comes to bite your head off