The answer is "perception." Watch brands who sell mechanical watches often place a premium on mechanical watches over quartz watches because all mechanical watches sort of want to be nearer in perception to beautiful hand-made mechanical watches.
At the top of the movement spectrum, are gorgeous hand-made and decorated mechanical movements that can take many months to produce. Your typical quartz movement takes just a few minutes.
Having said that, most mechanical movements that end up in watches people buy are closer to the mass-produced quartz movements in terms of their costs and production time.
From a price perspective, most quartz movements are half, or less of what mechanical movements cost. you can see prices of Swiss quartz movements versus prices of mechanical movements to see what we mean.
Alternatively, when a quartz watch costs similar to a similar mechanical one, brands must artificially price it low in order to justify the mechanical watch premium.
There have been tons of fantastic high-end quartz watches out there priced very fairly because brands don't want them stealing thunder from mechanicals.