Craft mastery and whyFollow

Some armor and weapons created by armor and weapon-smiths can be sold, not all of it though.

The advantage of becoming a master is that the items you can create (or at least some of them) are very good. For example, the weapons created by Blacksmithing Weapon Specialists (further divided into mace, axe, and sword specialists) are unrivaled outside of PvP rewards and raid drops.

You could always combine it with disenchanting and sell the shards 'n stuff, that can be a good influx of gold.

Usually, those 200-500g items are epic, and shard into Void Crystals, which usually only sell for 15g. Worse deal, even.

I would say that 90% of the gear you make is simply to level up your crafting profession so you can get to 375 and make those few pieces of gear you can wear that are comparable to raid epics, some even better that early raid gear.

If you cared to read the majority of threads about crafting and making money, it's been repeated time and again that crafting professions are not a good source of income. The are only 2 crafting professions that earn actually earn an income(when you compare the cost of the created item to the cost of the individual mats). The first is alchemy, the second is enchanting.

Enchanting is a funny crafting profession, because it comes with it's own gathering profession, disenchanting. As such you actually make more money selling the enchanting mats than you do selling the enchants.

Alchemy is another. You can make a small profit selling pots, but the profit margin is so small that it isn't worth it because your gold/hour income is worse that what you could be making by doing other things like dailies, quests and even simple grinding.

So in conclusion, crafting professions should be chosen based on what you want, not what you think you can sell. If you want to make money with professions, get two gathering professions.