The survival of the fittest.

"Bose is more successful than Tekton. Why?"

Bose is a real thought-through company with, over time, wide portfolio. They identified, if not created, markets that will be booming in the future and were well-positioned for them. Think noise-cancelling, "lifestyle systems", earphones, car audio, Bluetooth. Add a very strong marketing department and you have a successful company. What they make in Bluetooth speakers, they can afford to invest in truck seat development, I guess.

Tekton seems to be just a one line company (speakers), obviously much smaller and probably trying to inhabit a niche, rather than grow significantly. For all we have read, their admirable success has caught up with them and wait time is long.

Bose are successful because they are tuned to satisfy the vast majority of the public, mostly non audiophiles. Tekton is not very good as they use too many tweeters. Every speaker is tuned differently hence there are many companies out there because different people need different frequency response curves depending on their level of hearing loss. 

Bose = listening contour bef accuracy
Bose = 1 box simplicity consumers love
Bose = marketing, marketing, marketing
Bose = legal action against poor reviews
Bose = all for brand building and loyalty

In many ways Bose were Apple before Apple.

Expensive for what you got, but what you got wasn't necessarily bad.

Tekton make speakers, they are not Apple. They might not want to be.

Every company needs some luck with timing.

Bose got lucky. So did Apple. Many others did not.

The key words seem to be an impression of prestige, simplicity, and familiarity. All of which go towards establishing long term brand loyalty.

Once you have that, you've made it and it's yours to lose.

Isn't it Bowers & Wilkins, Sony, Harmon Kardon, JBL, Quad, Wilson, ATC etc?

For any of these established companies to fail now would require major strategic errors or some major shifts in the market place.

I agree with the OP in that actual sound quality is far from the main selling point.
Impressions and reputations count for much, much more.

You'd think that the iphone 12 would flop due to its outdated design, lack of innovation and poor battery life, but far from it. It's been a huge seller so far.

As I said, once you've established yourself, it's yours to lose. Even a minor misstep like paying way, way over the odds for Beats is only a hiccup.

Even Tim Crook knows that. 

marketing is king, being loose with review samples, the few rags we rely on need advertising to survive so when they don’t like a product that spends what can they do? Lie? Maybe just don’t review them or gloss over the negatives and focus on the parts they like, blame poor performance on associated equipment etc.

success comes from becoming a household name 

The survival of the pushiest.