Brand loyalty takes a while to fade, there seems to be a cycle with a large number of successful companies that goes
work honestly to build a good product
-> generate brand loyalty
-> people with integrity get replaced by people who would have had no chance of building that successful product/company in the first place
-> cut as many corners as possible while riding the brand loyalty to more short term profits
-> eventually, on the scale of decades sometimes (because people take a /long/ time to realize that 'well known brand' !== quality), get out-competed by a small company building the same thing as you with integrity
-> return to step one with new company.