Why is there such a high model turn over rate?

Most people who enter into the adult industry as performers do not understand the amount of effort that goes into making porn and building your brand. You have to run your career like any business. And quite frankly all the people who never even finished high school who get into the adult industry have no motivation to be anything better. They see porn as an easy way to make money. Their lack luster performances and reputation soon get them ostracized. I have had so many models book to shoot lately and cancel over and over. I rearrange my schedule and life for them. I want to give them every opportunity to succeed. (Which I was not given)  If this was any other job they would be fired, but since its not all I can do is choose to not work with them. So often I find models who seem so passionate about being in this industry, but their actions never live up to their passionate speeches. I do not know how someone can bitch about not making money when they have been given all the tools and repeatedly shown how to use them to their benefit. At some point you have to commit or stop wasting your time. If you aren't editing your videos and webcaming everyday of course you aren't going to make money... you aren't working.