> What's the difference between that which optimized for what you call "engagement" and what the average user wants?

People want joy, education, entertainment, etc. from watching a video.

But there may be other ways of appealing to people (addiction, insecurity, base stimulation) which boost engagement but which do not give users what they want.

Obviously on even slightly longer time scales, users will gravitate toward services that do not trade their health for engagement, but equally obvious is that many of today's apps are not optimizing for long time scales.

That's not what "want" means though

The average user wants to watch what they want right now. Netflix wants to surface shows that will keep you subscribed after you watch what you want to watch .

You will only stay subscribed if what Netflix surfaces what you "want" to watch

(Not OP) I can think of many ways where optimizing for greater watch time is unaligned and often opposite to making me happy and giving me what I want. In the case of Netflix, what I want might be to watch one show at a time for one or two hours every night. It may even for some people be about watching The Office or Friends, a show they know well and just watch for comfort. What Netflix wants is for me to start a completely new show (and probably one they produced themselves) every single time I open Netflix, and also to binge watch for six hours every night because I have “so many shows to keep up with.” This may not make me happy. But they suppose maybe it’ll make me more likely to keep my subscription.

What you want has nothing to do with what makes you happy

Netflix cannot make you happy