I was a United States Marine Corps recruiter from 1976-1979 and I never lied to anyone I enlisted. For example, if a kid wanted to be a helicopter pilot but dropped out of high school in the 10th grade, I would tell him the truth: you must graduate from high school, get at least two years of college, and then apply for flight school in the Marine Corps and even then, there is no guarantee that you will be accepted to flight school. My fellow recruiters called me, "hard core", because I refused to tell a kid that he could be a Marine Corps helicopter pilot with a 10th grade education, and frankly, I seldom made my monthly quota of new recruits. But, strangely, as poor a recruiter as I was, it seemed that my, "honesty, quality control, integrity, and knowledge of Marine Corps Recruiting Regulations", was enough to warrant my Commanding Officer to offer me the post of Operations NCO for the Area.
I did not have to lie to enlist anyone...the simple truth and a full understanding of programs offered and test results sufficed. I learned early that you never offer anything that you cannot deliver, and for an example...I received a phone call from a fellow in boot camp I had recruited who had an "MP" guarantee, and he said he received orders for Infantry! I took all of the pertinent information from him and made a call to Headquarters, United States Marine Corps, and was directed to a Corporal who was in charge of assignments. I explained the issue to him and within 24 hours, the fellow I had promised "MP" duty, had new orders assigning him to MP School.
So... the phrase I understand as... never trust a recruiter...should be modified to...make sure you fully understand what your recruiter is saying.
Recruiters are salesmen...they sell you six years of your life. If you don't understand that, then you had better ask your recruiter more questions because a good recruiter will have already explained that to you. When you enlist, you enlist for a period of six years with a portion of those years (2-4 years usually) on active duty, and the remainder to be served in the active, or inactive reserve.
Each service has guarantees, or programs, into which you may enlist depending upon your test scores, and being guaranteed you will go to a certain school may not mean that you will be assigned to that school's field once you graduate from that school. However, enlisting into a program means that you may be assigned to any one of the fields within that particular program according to your test scores. Make sure you understand the differences between schools and programs, and make sure your Recruiter explains them to you, fully.
I could go on and on, but I am afraid that I am well over 30 years out of touch with recruiting.
Educate me.