That's the hard part about designing software for anyone - there is no average user & you can't really make assumptions about their understanding of your system. After all, I think the intention of "My list" is clear and fairly obvious, so that makes 3 people with 3 different ideas about the feature.
I think the only on Netflix part works as part of positive reinforcement - it always shows me stuff it knows I watched all the way through (hence I must have liked it) mixed with things I haven't watched or haven't watched in a long time.
Thus when I see that section it is reminding me they have stuff I liked that I can only get there so please don't ever change account, and here is some more of that stuff only we got - try it out!
It seems some shows have been trending for years.
Or maybe it's not as simple as you think? "Baffled" is a strong word. It's the same "baffled" that Amazon can't find all the fake reviews. The same "baffled" that Facebook can't delete all your photos, everywhere, when you close an account.
Maybe things at scale are more challenging? These are some of the most valuable companies in the world. I'm sure they're happy to throw buckets of money at you if you can solve these "simple" problems for them.
I just went to the frontpage of my Netflix and...:
- "My list" recommends 3 series where I have alread watched the last episode
- "Only on Netflix" recommends another two series, I have already wathed.
- A section displayed is "Watch together for older kids" - I dont have kids, never watched any kids stuff on my account.
- "Documentaries" contains six suggestions, 3 of which I have already watched on netflix".
- I am suggested several shows, which are good - but I have already watched outside Netflix earlier - and there is no way to tell Netflix (none that I know of, anyway)
9 out of 10 times when I go to Netflix, I intend to continue watching a series - but Netflix makes me scroll past SEVEN sections of recommendations to get to "Continue watching.." before showing me the series I have watched 1-2 episodes of most days for the past two weeks.
Maybe they are just too busy making sure all new series are woke-i-fied to care about how this simple stuff works?