The Harbeth phenomenon

In my search for a new pair of speakers, I've gone through many threads here and noticed that many owners or fans of Harbeth have almost a love-like connection with Harbeth speakers. It is almost as if the speakers cast a spell upon them. I know many audiophiles love their speakers but Harbeth owners seem especially enamored with theirs. I am extremely puzzled by this phenomenon because on paper Harbeth speakers look average at best and lack many of the attributes that generally make a great speaker.

Their sensitivity of generally around the 86dB mark makes them rather inefficient and therefore, at least in theory, not a good match for many lower powered tube amps, or any amps below 100wpc. Their frequency range is simply inferior to most high-end speakers since they don't go below 40 Hz. This alone should, again at least in theory, disqualify Harbeth speakers from consideration as top high end speakers. And yet I've never heard anyone complain about their bass, while people complain about lack of bass in the Gibbon Nines from DeVore, which is a fantastic speaker. Their cabinets look like a cheap DIY enclosure (disclaimer: I've never seen a Harbeth up close, only pictures). The 7ES-3 is rated B-Restricted, while the smaller and cheaper Usher Be-718 A-Restricted in Stereophile but garners nowhere near the same amount of admiration, praise and following among audiophiles.

So what's going on here? Is this a big conspiracy plot by the company that paid off a few hundred of people to infiltrate audiophile internet forums and a few reviewers? I am of course joking here, but the question is serious. How can speakers so average on paper be so good in real life? I know the opposite is often true, but you rarely see this phenomenon.

Please speak up.