Many would say having a six pack has many benefits and a indicator of health. In a few cases that is true, low bodyfat can be an indicator of health but how low is too low and where does the balance formulate to say someone's healthy? A great six pack shows you've worked hard to build the abdominal muscles and made strides to make yourself look good which by itself isn't a bad thing, however; does those muscles help minimize or prevent injuries as much as possible? Can it take a hit? Is it strong enough to work the Stabilizers? Is it conditioned?
These are the questions I look for when I see those with a six pack. Seen some strong people that look average and seen bodybuilders who can barely walk, plus crackheads have very low abdominal fat and have a six pack at times so where is the line drawn that a six pack meaning something healthy? The truth is, because we're all different, our bodies don't always develop the same way as others but it is important to understand it's not always the abdominal muscles that should be looked at for an indicator of health, it's the entire realm of the Core (abs, low back, obliques) that should give you an idea of how strong it truly is.
Core Strength is one of the true indicators of how healthy a person is. You can have extremely low bodyfat and still have a weak core structure. Being able to twist and turn without hurting yourself gives off some strong vibes there along with utilizing those muscles in how you perform your workouts. The tension vs the relaxation in your performance. Understanding how to brace yourself as you control a movement or hold. Think of Gymnasts, the control over their bodies is one of the most fascinating things about the human structure. The way they can move and hold positions on the Rings, swing on the High Bar, flip in the fucking air during a floor routine or on the vault, its captivating and eye popping. Sure this is sports specific but it doesn't take away the fact that if they couldn't control the way they do things, they would be crippled for life.
The greater your strength is in your Core from a certain POV, the stronger you'll be not just physically but overall. It's one of the reasons I train a lot with Isometrics, Suspension Training, Sandbags, Bands and Hammers....In order to perform these methods well or even to get a pass by, I need to be in control of my Core otherwise I'd be injured a hell of a lot more. Core Strength goes beyond just doing Abdominal Exercises, it's about creating a strong foundation to what is needed for things in life that can be a saver for people. Hauling furniture takes Core Strength, doing Farmer's Carries takes Core Strength even when you're off balance, moving in awkward positions without injury starts with Core Strength.
Having a strong Core may not always be obvious just on appearance alone, again, you can look like a million bucks but do you have the strength and control that comes with it? That's the true indicator there. Keep yourself strong and healthy and keep being amazingly awesome everyone.