When you first begin sales, you may have to work a little longer than required (this is optional, not required) but it definitely plays into your success.
All sales jobs have a high turnover but the difference with PLS is that you determine how long you will be here. You work hard and do what you need to be successful and you will hit your goals, if you don't work hard then it makes it a lot harder to hit your goals and that's where the turnover comes into play.