Indeed. It is for sure possible to have an inefficient and non-resilient system. But I think the general point that efficiency tends to trade off against resilience is an important one which too few people understand. (one specific example from queuing theory which I wish more people understood was the tradeoff between resource utilization and latency. If you want something or someone to be busy almost all of the time, there must be a long queue which increases the latency of access, in the limit getting to 100% utilization the expected queue length grows without bound).