I wonder if MMOs will ever move on from the archaic system of "1% success rate, if you fail you're shr3k'd m9". Tera used to have a system where if you fail enhance, you have better chance at success the next time. That would be optimal but most game developers are too hungry for money of desperate players to implement such system.
Aura Kingdom had something similar too. There is something called "potential", which has a 100 points limit and every time you fail enhancement you'll get a value based on your current upgrade level, so it'll take a maximum amount of attempts to get your item done.
Now, SW is not even clear about the enhancement chance. They should at least add a label showing it.