Putting too much effort into it. Protein, vegetable, fruit. How is it so hard to make aportionx6 with that?
Telling people not to count calories unless they're athletes is silly. Maybe I'm wrong, but you sound like someone who has been in pretty good shape for his whole life, or at least someone who was never really, really fat.
I bolded the key word in your quote: portion. How big, exactly, is a portion? I guarantee if you ask some fatty what a healthy "portion" of chicken is, he'll tell you something WAY more than you would consider eating. It's hard to know what a "portion" is unless you count calories for a little while to figure out how much you should be eating. For example, until I started counting calories I had no idea how big a "portion" of chicken should be. One of the big reasons so many people are fat nowadays is because a "portion" for most people--even of lean meat--has become way bigger than it should be, which provides way too many calories than are needed. If you've been relatively fit and healthy your whole life you probably don't have a problem with this, but for people who used to be fat (i.e me) you'd be surprised how skewed an idea of what a "portion" looks like we can have.
When I first got serious about getting healthy and started counting calories I was
shockedat how many calories were in stuff that I'd considered "healthy" before. Before, a "portion" of brown rice for myself was probably 2 - 3 times more than what I should have been eating...but I had always been told brown rice was healthy, and I was eating the same amount I'd get in restaurants. I, like most fat people, knew fuck all about what healthy eating really means.
Once I counted calories carefully for a few months I learned about how big 250 calories of chicken looks, and 300 calories of rice, etc. so I'm able to easily eyeball it now without going too far under/over my "portions". But unless I had counted calories in the first place I'd have had no idea how big the meals I was eating should be.
So there's no reason to count calories for an eternity, but it is hugely useful to do for a while in order to learn just what "healthy" amounts of food look like.
*Edit* I will agree that it is silly to focus on body fat percentage and even scale weight. The only things that matter should be 1) how you feel and 2) how you look. Body fat percentage is infamously hard to accurately measure, and scale weight is incredibly misleading.
*Edit 2* Just in case you ask me, yes, I'm in decent shape. Not pro athlete level or anything of course, but above average for a late 20s guy (judging by what my peers look like).