I have notice salt concentration is less depending on when you add salt to your soup.
If you add 2 teaspoons of salt before boiling your soup, after your soup has been cooked you will notice it tastes less salty compared to if you add it at the end. Even if you add it at the end and REBOIL it still tastes far more saltier.
I am not using any vegetables at the moment I am just using chicken. Is it because the chicken is absorbing most of the salt if so why doesnt it absorb it if you add the salt later and reboil.