Good trainers customize your fitness plan the same way you'd plan a trip.
You pack, map your trip, and do some basic planning to prepare for a great vacation.
A good, honest trainer understands the value of prep work too, and that begins with a personalized fitness assessment.
Trainers who don't conduct a proper assessment are lying when they say they're building a customized fitness plan
Why? Because it's literally impossible to customize a fitness plan unless you're fully familiar with your client's strengths, weaknesses, and their very specific training needs based on their personal abilities.
That's why you hear about friends who blow out their knees at CrossFit. Or family members who hurt their backs at gym classes, or using streaming fitness videos. They're working in spaces that don't provide this important information.
But the absolute worst is when you hear about someone who hired a trainer for proper guidance and STILL got hurt because their plans weren't guided by a proper fitness assessment. And unfortunately, most trainers overlook this critical first step.