I'm not sure about what glib phrase I would use (say, consisting of just two words) but the main idea in the overall approach is that we stay on top of critical bugs. If we have critical bugs, we don't do anything else until they are solved. We don't polish the chrome on some shiny new feature, while a fire is raging. So this is "Bugs First" or something. Except it's not all bugs first, just the showstoppers. "Fires First?" Hmm, what's a glib word that clearly means "show-stopper defect"?

Another way to approach this is from the angle of: no customer is left to dangle in a situation where they aren't getting value from the product, where they are faced with an issue for which there is no feasible workaround, or some security breach. What's a glib phrase which quite precisely conveys the idea that try to prevent this situation at all costs, and get them out of it ASAP if it happens?