Why does FaceBook stock have value?

[YahooDeana]

So many I know are deleting (or suspending) their Facebook or don't use them so the number of members (which is what drives the value of their stock) is not accurate regarding the number who will see advertising.
To me Facebook is like a Never Ending Holiday Letter - so its trend will have to get old someday soon it seems. ?

[Zarn]

You're doing a classic mistake - not discerning between the actual stock value and your own, incident-based idea of what the value should be. It is true that Facebook's user base is changing, and that some are nixing the use at all. That's why the stock is currently trending downwards. Is that the same as the stock being worthless, and that the service that Facebook is delivering is irrelevant? No.