Every social network: you make something for your friends and end up with viral growth immediately or after years of nothing. You spend the rest of your days policing trolls, spammers, and scammers trying to abuse or hijack the network. You or someone in marketing send out too many spammy notifications abusing user trust and users block your notifications. Nobody shows up
anymore and network dies.
Every rom-com: Boy meets girl and they have good times. Somebody messes up. They have a fight. The get back together again.
Every Hallmark movie: Big city girl ends up in small town by coincidence. While decorating for Christmas she falls for the small town guy and decides to stay. (The productions get cheaper by the year, so where they had scenery you now see people talking in front of a blurry background for 90% of the plot. )