The power relationship between designer, corporate CEO, and the marketing department are different for every company. Quite a few well-known high-end companies (not going to name names here) are little more than marketing departments, hiring designers on a as-needed basis with no engineering continuity between projects. The engineering staff is basically a revolving door, resulting in products that might sound good, but not much follow-through as older products are phased out and the original designers are long gone. When you see a lot of "churn" from year to year in the product line-up, that’s what’s happening behind the scenes.
If the marketing staff are the only element of continuity in the company, the products may physically look the same from year to year, but what’s inside can be quite different. This is especially true if parts of production are moved offshore, taking QC and service support with them.
If the founder, or spokesperson, don’t understand how their products work, there will be a superficial continuity, but the new-hire designers will have trouble understanding the previous products on a deeper level. The schematic doesn’t usually tell the whole story, and the previous designers may ... or may not ... have documented the design philosophy of what they were doing. We’re not talking about Apple-sized teams of scores or hundreds of engineers here; no, more like one, two or three people per audio company.
This is why I said in the previous post to pay attention to the designer, not the name of the company. If the company is the size of Apple or Microsoft, there is a continuity of engineering culture over the decades. This is not true of audio companies, where engineering "teams" are often no more than one to three people, so if they leave, basically nothing is left.