When seeking optimal health and event to look great, it's easy to neglect how important it is to maintain basic function of the body; you can move around, accomplish the physical tasks you choose, and not feel beat up all the time.
And this makes sense. After all, for most people, if you're able to get around during the day and you're not in pain, there may not be a reason to think about your body much beyond that. Furthermore, if you're active and "fit," you'll generally presume all you need to do to stay that way is keep coming to the gym and sweating.
Unfortunately, this isn't always the case and it may be a while before you feel the effects of creating movement by using your muscles in an unbalanced fashion.
A car is a good metaphor here. If you're never changing the oil, you don't warm-up the car on cold days, and the alignment is off, you'll probably be fine for a while. Until you're not.
Your body is not a car. You can't drive a hire car while it's in with the Mechanic, and you can't just purchase a new one.
But it doesn't matter how strong an engine is if the wheels fall off the car. And it's not uncommon to see someone with major horse power who's driving around with a flat tyre.
This is part of why a quick overview of what's going on with someone's movement quality is important.
To be clear, we're not looking for perfection. Your body is designed to deal with asymmetry. If your goal is to get fit as fast as possible, we're not going to make you do a bunch of unwanted technique work if you're moving ok, because we want to get you to your fitness goals as fast as possible.
That said, if you unknowingly have a full-on flat tire... we got to fix that stuff. In the long run, it will be faster to take the time to take care of that situation, even if it means a momentary detour. If we DON'T fix the situation, and we just start training hard, there's a real good chance pain will follow; the flat tyre will get flatter and bad things will happen.