But HN has a persistent bug where the next button on the first page expires and doesn't work. That's the difference between doing something for work and doing something for fun.
There's the same 'feature' which works against insightful commentary. Spend too long crafting a response, get "unknown or expired link". Not particularly endorsing of a considered, pensive response.
Surely there are better ways. For example, you keep track of which posts a user has already seen, and when they hit the next page button, show them the X most highly ranked posts that they haven't yet seen. Breaking the link is just the easiest way to deal with the problem.
But HN has a persistent bug where the next button on the first page expires and doesn't work. That's the difference between doing something for work and doing something for fun.
The willingnes to tolerate malfunction is higher