Useful but not sufficient on its own. Gresham's Law, in various incarnations, including Akerlof's "The Market for Lemons" suggests limitations.
A trusted third-party reviewer (Consumer's Union, CarFAX, Kelly Blue Book) helps.
Anecdote: the last really big-ticket item I bought (automobile), I'd had positive experiences with two manufacturer's products previously, but really didn't care for their current offerings within the product class / price range I was seeking. The vehicle I did buy was one I considered based on its Edmunds review -- best in class, multiple years running. Some years on, I've been happy with the purchase (though of course, post hoc rationalisation is a common fallacy).
For other products, other signifiers matter.
On G+ I detailed frustrations looking for a decent LED cabinet-lighting system. I'd exhausted local, online (Amazon and major hardware/lighting store) sources. A recommendation from my G+ contacts was for Ikea. The specific product didn't work, but Ikea had another set of lighting components (separate cord, transformer, remote switch, and lighting elements) which has worked excellently. Took a few weeks longer than intended to find what I was looking for.
Otherwise, I rely strongly on what local retailers will carry and stand behind. Ikea, for some products, turns out to be a good source. Factors depend heavily on what it is I'm purchasing and just how it will have to function.
I'm sure the failed entrepreneurs in this crowd (I'm one of them) here will find it easy to refute that point.
High-quality product is nothing without leads (i.e, potential users, buyers, downloaders, etc), and one way to get consistent, reliable way to get leads is through promotion.
Then there's branding and awareness, which is probably what most ads these days are meant for.
A trusted third-party reviewer (Consumer's Union, CarFAX, Kelly Blue Book) helps.
Anecdote: the last really big-ticket item I bought (automobile), I'd had positive experiences with two manufacturer's products previously, but really didn't care for their current offerings within the product class / price range I was seeking. The vehicle I did buy was one I considered based on its Edmunds review -- best in class, multiple years running. Some years on, I've been happy with the purchase (though of course, post hoc rationalisation is a common fallacy).
For other products, other signifiers matter.
On G+ I detailed frustrations looking for a decent LED cabinet-lighting system. I'd exhausted local, online (Amazon and major hardware/lighting store) sources. A recommendation from my G+ contacts was for Ikea. The specific product didn't work, but Ikea had another set of lighting components (separate cord, transformer, remote switch, and lighting elements) which has worked excellently. Took a few weeks longer than intended to find what I was looking for.
Otherwise, I rely strongly on what local retailers will carry and stand behind. Ikea, for some products, turns out to be a good source. Factors depend heavily on what it is I'm purchasing and just how it will have to function.