You both are right, and I know that this goes on. Why do you think that is.? There are some good theories out there, but here are some that I know of for sure from speaking to graduates who left us, in no particular order:
1. I got tired of being "on call", I needed a more steady start time.
2. There are too many negative people and I got tired of listening to it.
3. ABC company pays better.
4. ABC company offered me P&D right away.
5. Too many rules to remember, everyone is too strict.
What I have always tried to do with applicants is paint the ugliest possible picture of their first couple years for them. I also intentionally go after the 9-10 dollar an hour warehouse worker who has forklift and loading experience under his belt, but is stuck with no advancement opportunity and wants a better life for himself. This part is not meant to sound discriminatory, but it will: preferably the young married guy with the first baby on the way, or with a couple of small children. He is the perfect candidate. Our package is very strong for the young family. However, that being said, my schools have ranged from 21-53 years of age, matters not if I see the value for Con-way in anyone. Sometimes that 50 year old brings the excellent mix of maturity and level-headedness that gives the rest of the class someone to look up to and follow.
Lastly, everyone in the service center has to be behind the program and willing to help the newbies at every opportunity. The guy with 15-25 years experience is the prime time guy, so to speak. I am gifted with many who fall into this category and who understand the importance of teaching the new guy the "correct way", because they know they will benefit from it as well. When they do that, the odds of keeping your graduates climb dramatically.