Definition:Grinding

Grinding is defined as repetitive, uninteresting, and often simple activity which serves to increase the player character's experience points, monetary gain, and other useful or necessary items. Naturally separate from playing the game normally and getting stuff because of that.

Most often takes the form of killing enemies to gain experience so your character won't get decked by the much stronger enemies you'll encounter later on. If the game developers are merciful, they'll hand out EXP generously to avoid grinding. If not, the devs are trying to trap you in their cave of 50-hour content schemes.

Rationale
Grinding is not an innately difficult concept. Instead of performing a single, high risk, high reward venture in order to level up, the player will do a large amount of low-risk, low-reward tasks to achieve the same end. Because of the repetition, games that feature large amounts of grinding tend to be boring. It's the enduring of the monotony that is difficult for players, and why it is an important aspect of a game's difficulty.

Generally, ratings of 1s and 5s are rarer than the other ratings. Consider this when rating games.

0 stars
Does not include grinding in any capacity. These are mostly games that have no level or meaningful reward system, such as puzzle games and most first-person shooters.

Use on game pages.

1 star
Grinding is possible, though discouraged or considered unnecessary. Games that have low level requirements or have anti-grinding features are around this area, making attempts to grind either inefficient or impossible after a certain point.

Use on game pages.

2 stars
Grinding is one of the methods the player can use to advance, but it's generally ousted in favour of other level advancement features, such as performing quests or advancing the main storyline.

Use on game pages.

3 stars
The game encourages equal amounts of grinding and other forms of advancements, through giving out equal benefits for both or through prioritising both methods during certain times. A player who focuses on one over the other may find themselves at a disadvantage.

Use on game pages.

4 stars
Grinding is heavily encouraged to advance the game. Although there may be other ways to advance, it is generally the most efficient or least-effort endeavour for the player.

Use on game pages.

5 stars
Grinding is the most necessary and defining element of the game. It is required for any meaningful game advancements, limiting the freedom of the player.

Use on game pages.