Every single item used in crafting or resulting from a crafting recipe has a grade attached to it. Grades range from F (worst) to A (best) and also have a sub-grade ranging from 0 to 9. Combining both of these values you get a Grade value from F0 to A9. If the end result is something that can be used, such as a Fitting, it impacts the actual stats on that object as well.
If you are just beginning to make a certain recipe you will find yourself creating F to C grade results based on the ingredients. As you increase your skill level, you'll achieve better results. Additionally, every time you create an object through a recipe you also have a chance to increase your mastery of that recipe. Receiving the higher grade results will require both high quality components, and much practice with that particular recipe.
An important part, as mentioned before, is the quality of the ingredients in the recipe. If you use poor quality ingredients the result is going to be poor itself. Ingredients come from sub component recipes, store purchased ingredients, and extracted resources.
You may obtain a recipe within your first few minutes of gameplay, and that same recipe could still be useful two years down the road. This works by requiring a generic ingredient such as Tissue, and then allowing players to fill its requirement with any of dozens of types of Tissues, each producing different results. The recipe might focus on creating a damage fitting, but based on the ingredients it could adjust how balanced the fitting is, add certain types of damage, or adjust the level required to use the fitting. Results can also change based on the grade result, allowing for a totally different result from C to B, or B to A as well.
Recipes are made up of one or more Ingredients and one or more Agents. Ingredients are the main "filters" for creating a recipe. The result of the recipe can change based on the Ingredients used. Ingredients are not consumed until after the whole process is finished. Agents have a smaller role in the process but are burned through on each step. Agents primarily impact the quality of the end result in a minor fashion, where ingredients have a larger effect. Each recipe has a set number of steps, and during each step there is a chance for an event.
Events occur randomly during a crafting session and can have a positive or negative affect. You can alter the result based on how you respond to these events. Crafting tools come into play here. Crafting tools impact which events will occur and how you can respond to them. All events have a 'no consumption' option where no item is consumed, and the event is skipped over. Each event has at least one other option that requires an item to be consumed. This will produce two different results based on if it succeeds or fails. Some options require a specific tool of a certain quality to successfully chosen, as well. Crafting events can be positive (such as an increase in total grade) or negative (reduction, lost a step, or even a total failure). Players are presented with risk/reward options and can make their own decisions on if the rewards outweigh the risk.
Great crafters aren't born overnight, and there is a need to hone your skill, just like any other game. People may not be lining up to purchase your D grade results, and that's where crafting missions come in. Crafting missions allow you to fill work orders from NPCs by crafting the items they require. Your reward for the mission will vary based on how difficult the recipe was to create.
Tasks can be generated based on your skills levels, and this includes your trade skills. Crafting missions can be tailored to your specific skill set. This is a good way to learn how to create different recipe results and get a little more out of your sub-par results while you skill up. These missions are completely optional.
Crafting Board Edit
The crafting board can be best thought of as a reverse auction system. Instead of putting your results up on the auction house, someone places a request for a certain result along with a level and grade restriction and sets a price. Once the request is placed, everyone gets a fair chance to fulfill the order.