Ask someone to hand you a facial tissue and they hand you a Kleenex. Ask them to photocopy a page and they Xerox it. Ask them to look something up and they Google it. In each case a proper noun has quietly eaten a common one. That is not an accident of usage. That is the objective.

Branding is the deliberate work of conventionalizing an abstraction. You take a specific descriptor (facial tissue, photocopy, web search) and you spend years and fortunes training people to reach for your name instead. The brand wins when the reference overwrites the referent, when the category disappears behind the label and nobody bothers to look for it again.

The tell is substitution

Most marketing measures awareness. The sharper measurement is substitution: how often does your name get used where the generic word belongs? That is the moment the abstraction has set. People are no longer choosing your product over a rival. They have forgotten there is a category to choose within.

• Kleenex for facial tissue: the tissue is now nameless.
• Xerox for photocopy: a verb wearing a corporate logo.
• Google for search: the whole open web collapsed into one door.

A brand hasn't peaked when everyone knows it. It has peaked when everyone forgets there was ever a plain word for the thing.

This is powerful and it is fragile. An abstraction that fully eclipses its referent also inherits responsibility for it. When the brand degrades, people experience it as the category degrading, because to them the two are now the same word. Own the abstraction and you own every disappointment filed under it.