[oytis]

I understand it as being about technical decisions rather than interests. Engineers are inclined to make architectural decisions that align with their idea of what is fun to do. But really fulfilling work is the one that is being used and serves the purpose.

Say I've seen a QA engineer designing an elaborate formal verification framework that took a lot of time, but failed to test anything engineers or customers cared about. Can't tell if he himself was happy with the result, but I wouldn't want to be in his shoes.