Objectives

Goals

Goals in gaming are points in which a player must reach to advance or finish the game. A game can set multiple goals to keep a player entertained thought, these goals can be as simple as going to a certain place or picking up a required item, or they can be long and a bit annoying, for example a quest could ask you to kill a certain amount of creatures using a specific method which is hard to do. 

These harder goals are usually side-quests though, a side quest is a quest taken on along side your current goal. Side quests are goals that are not necessary to complete a game but in some circumstances can improve the overall game or the game ending, this could be by providing the player with better equipment, giving the location a player is defending better chances of surviving etc.

In a game a singular part of it can be made of multiple goals, in a linear FPS these goals can be consecutive meaning that as soon as you complete one goal you are given another as objective are updated and you continue the mission, whereas a sandbox games may give you a couple of objectives at once and you can choose which you go for first, or they may have a time limit on them, a classic example of this is dead rising 2, in this game you are given several goals and a time limit for each, including an over all time limit.

Goals are important as they give the player a sense of meaning in the game, they are given objectives to save a world or to help those who need it. This sense of meaning is important as otherwise the player will wonder aimlessly trying to make sense of a game that can't provide anything.

Challenges

In games challenges can be set for raising the players level, giving the player extra equipment or in game money or set for fun. Challenges can be ranged from completing a certain goal or zone in a certain amount of time or defeating an enemy in a very tasking or comedic way. A great example of these challenges are Mario Kart ghost races, daily, weekly and monthly challenges on Halo 4 and general challenges in Hitman absolution.

Challenges are important to a game as it adds an extra bit to a game, challenges allow players to re-visit previously completed levels and complete the, in different ways or using certain items. Challenges also allow the player to use a certain item and get a set amount of points with that individual item or a group of similar items.

Rewards

Rewards in gaming are used to convince a player to complete a certain goal or challenge, these rewards can range from extra money to valuable equipment for the character. Rewards make a player want to complete a challenge as if they don't know what the reward is the player may be curious or they may see what the reward is and want it.

Rewards are also given by completing goals, these rewards are likely shown when the player is excepting a quest or mission, an example of this is borderlands 2

Rewards are important in games as they push the player to complete the goals and challenges so they can obtain the this new reward. This also includes experience points for the character, which levels them up quicker, this is useful for leveling up your character when you're in a difficult spot in the game so you can take on some side-quests to earn extra experience or in multi-player to unlock new weapons, abilities or apparel pieces.