To say that good measurements guarantees good sound both misses the point and is silly. There are too many things going on that either cannot be measured or at least cannot be measured with the equipment available to most hobbyists. The reverse, if everything can't be measured, than all measurements are worthless is equally silly.

There are any number of things that can and will go wrong with an audio system in any reasonable listening room. Properly taken measurements can help eliminate reflection, resonances and large deviations from flat in the room and in the speaker itself. Once the incidentals are taken care of, then the listener can make judgments as to whether the system has that magic or not. "There are liars, damned liars and statisticians". (Mark Twain) Those who rely solely on measurements are statisticians. Measurements are only a tool, but a very valuable tool. At least in the process of building audio components, doing without measurements is going in blind.

Bob