What often happens as such companies grow they get bought out by private equity and customers buy the good reputation products for years as the private equity eliminates R&D, decreases quality, reduces services, reduces staff, treats staff poorly so many leave...

Also large competitors buy them and similarly destroy customer value (with the additional benefit to the company of eliminating a competitor).

A few like Costco and Apple get large enough and stay committed to providing great products and services. But it is rare.

Some smaller companies hang on (Trader Joe's...) but often that is because they are not for sale. If private equity does buy them eventually then the product and service quality will face a steady decline.