THE PATH ITSELF.
Alchemy has been practiced for centeries and centries. This practice take a lifetime to learn, and a life time to master, because of it's knowledgment, you must combine science with magick, you must know the difference between fake and real. This path isn't mastered by everyone who tries to follow it, some people quit because the path takes forever to learn, they are called the alchemy drop outs.
Alchemy takes faith and plus knowledge, what you know is that it turn silver to gold and other things, but alchemy is more powerful then that. Alchemy is more mysterious then that. Doing alchemy in assumption that you can be rich is wrong..Alchemy isn't for making your rich it's for making change. Understanding alchemy is a strong role which some people who study it don't understand. You think you can turn even rock to gold, well you wrong, because there is a cycle which it works, this cycle keep alchemy in check, and keeps your minds flowing.
WHY ALCHEMY TAKE A LIFETIME TO MASTER.
Alchemy is a tuff path to follow, because there are many books and many things to learn, it masters both magick and science, you must have years of experience in science and also years in magick to successfully use alchemy in every day work. Learning this path isn't as easy as some people make it seem. Alchemy is dedication, alchemy is one of the hardest paths to follow, and almost 50% of those who follow this path pass while the other 50% drop out of alchemy because of the long rate.