What makes a game...good?
An interesting question. There are a number of aspects that make a game 'good'. Let's start with the challenge versus reward factor.
Challenge Vs Reward
If the game is too easy, the player will get bored. If the game is too hard, the player won't continue to play it. If the game is challenging, but there is no reward for completing a task, the player won't continue to play it. If the game is quite challenging but there are too many rewards for completing tasks, the player will feel no joy in accomplishing goals, and so they will not continue to play it. If the game is easy, and there are too many rewards, the player won't continue to play it. If the game is easy and there are no rewards...well you get the idea.It is vital for a game to tread the thin line delicately to produce gameplay that will be both challenging and rewarding in a ratio that will keep a player interested. This is an element of balancing a game. Balance will be addressed further at a later date.