Experience is Important, but not Enough
What do you picture when thinking of a personal trainer? Someone with a great physique who lives in the gym, does the occasional bodybuilding competition, and survives off of chicken breast and steamed broccoli?
While, it's important to lead by example, the majority of "real people" who truly need assistance with their health are those suffering with nagging injuries, cardiovascular issues, and have no where near the tolerance level to handle the "bootcamp" style fitness routines offered in nearly every gym or personal training studio these days. The "real people" are left behind.
It's rare that a young personal trainer has personally delt with extreme dysfunction or had to rehab their own knee, spine, or immune system back to health. They often deliver exercises based solely on their own experience. They just cannot relate to those who "just CAN'T do it."
Experience is important, but it's not enough. Motivation is important, but that means more than being a tour guide/rep counter. Are you getting expert advice based on a thorough understanding of your structure and mechanics or is the information from your trainer simply things that were passed along from other trainers, opinion articles from the web, and social media?