Grinding
Grinding is a pattern that forces users to repeat the same process several times to unlock an achievement. This pattern has been classified as a “temporal dark pattern” as it forces users to commit more time to a digital service or platform than they expected or planned. Digital services use Grinding to consume the user’s time and attention by increasing engagement and promising a later award, such as a new level in a video game or a badge on a social network.
Example: World of Warcraft

In massively multiplayer games, such as World of Warcraft, where players are forced to spend more time in the game for the sole purpose of extending the game’s duration. This is often achieved by requiring players to repeat the same process (such as killing monsters to gain experience points) to unlock an achievement or advance to the next level.
Example: Twitter

On Twitter, the verified badge can be achieved if the account is notable and active, with a sufficient number of followers and mentions. This encourages users to spend more time on the platform, trying to gain more followers and mentions to achieve the verified badge.