First you looked "very athletic" at 170, now your abs were "slightly defined" at 160. Uh huh. If that means anything, that means you had a lot of visceral fat, or it's more stored in the legs.
And well, it's WAY past the edit window now. The next time you are at 160, I recommend using the tape measure to measure things like waist to chest circumference, and thigh circumference. Then ask if those measurements are bigger than what can be explained by the muscular performance you get. Another thing you can do is try jumping rope, running in place, or doing jumping jacks. When I do these activities, I get "jiggle." My moobs and stomach get jerked around, because there is some flab there. The effect lessens as you lose weight.
What is not objective is looking in the mirror in some lighting and thinking you look pretty good. That's a subjective measurement based on objective reality. Your body might distributed fat in a way that's relatively aesthetically pleasing -- mine does too, it hides it all in the thighs, and people think I'm way more in shape than I am -- and that's not the same thing as being healthy.
What is not objective is looking in the mirror in some lighting and thinking you look pretty good. That's a subjective measurement based on objective reality. Your body might distributed fat in a way that's relatively aesthetically pleasing -- mine does too, it hides it all in the thighs, and people think I'm way more in shape than I am -- and that's not the same thing as being healthy.