there are many examples of critters that never made it. (Several early tetrapods had 8 "fingered mitts" and these persisted for millions of years . Eyes with crystal lenses or no focus mechanisms is clearly seen in many fossils yet these species were often more successful than we have been.
You are measuring "efficacy" as if it was a goal, and really its not. Efficacy has often been nothing more than a compromise for an adaptation for something entirely different than what it shows up doing.
Evolution has always been a record of fits and starts and really dumb design and "making do". because almost every root functionality had been clearly defined by the time flatworms developed, genomes either grew gene by gene or "cosmic hedgehog" trimmed its function yet the gene remains as a fossil on the organisms gene structure