Each game itself is mostly throw-away (although a few have some impressive graphics bling which must have taken some effort). I've been watching a channel called "Idle cub" [1] and he posts a new game every day (well, almost, sometimes he'll play a demo and then later the full game).
Seeing a massive stream of games that all surround the same 12 or so mechanics has been eye opening. The games range in duration from ~2 hours all the way to several days of content, although most premises seem to get old at around 4-6 hours.
At first I was doing research for my own game ideas, now I'm kind of mesmerized by the variety and the general relaxed atmosphere of these idle games.