When a PC fails a roll, there’s always a consequence in the Mutant games, like in Burning Wheel but you’re not obligated to negotiate it first. Soo if they eff something up in a habitat where I’ve sent a Watcher patrol, well, then it’s the patrol that gives them trouble. But if I haven’t assigned any Watcher squads, then I look at the r-map for a suitable NPC. If the fiction doesn’t fit in either case, then I think about more natural fictional consequences.