That's a bit oversimplified. The ACT approach is that goals can be useful things, in moderation, when they're serving your values. But if you get too caught up in the outcome associated with the goal -- whether you succeed or fail, whether anyone recognizes or not -- then you're likely to have problems.
For instance:
"My company failed. This is a disaster. I'm such a loser."
"We beat our sales target by 200%! We're geniuses!"
"After months of work, we finally shipped. Now I feel empty and have no enthusiasm for what's next. Why aren't I happy?"
(Of course those are oversimplified too, but you get the idea.)
You are correct. It's been a while since I read these books. Looking back at Harris's book (The Happiness Trap) he has an entire section of the book dedicated to values, and he stresses that values are more important than goals. But he does still say to set goals.
For instance: "My company failed. This is a disaster. I'm such a loser." "We beat our sales target by 200%! We're geniuses!" "After months of work, we finally shipped. Now I feel empty and have no enthusiasm for what's next. Why aren't I happy?"
(Of course those are oversimplified too, but you get the idea.)