Look at almost ANY arcade game of the 70s/80s. Most of them weren't designed with an end in mind. You play as long as you can for the accolades that come with posting your initials on the scoreboard.
Asteroids is a quintessential example - relatively flat difficulty curve once you've mastered the game - it really comes down to a test of the player's endurance. Scott Safran set a record game that lasted a grueling 60 hours.
EDIT: Anyone who has EVER tried for a high score (whether a personal best, or a world record) is familiar with the natural nervousness that increases in direct proportion to how close you are to breaking it. That's not a Flappy Bird thing, that's a literal every game thing. Go watch a live stream of a speed runner that's got a heart rate monitor attached to the feed for example.
Asteroids is a quintessential example - relatively flat difficulty curve once you've mastered the game - it really comes down to a test of the player's endurance. Scott Safran set a record game that lasted a grueling 60 hours.
https://en.wikipedia.org/wiki/Scott_Safran
EDIT: Anyone who has EVER tried for a high score (whether a personal best, or a world record) is familiar with the natural nervousness that increases in direct proportion to how close you are to breaking it. That's not a Flappy Bird thing, that's a literal every game thing. Go watch a live stream of a speed runner that's got a heart rate monitor attached to the feed for example.