In there it clearly states that it is because there is no electronic tracking system of any kind. They're trying to figure out the estimates based on paper records.
I would suggest that you take a look at the guidelines[1] for hacker news, which I believe set a good standard for productive discourse. Particularly:
> Please don't comment on whether someone read an article. "Did you even read the article? It mentions that" can be shortened to "The article mentions that."
> Please don't comment on whether someone read an article. "Did you even read the article? It mentions that" can be shortened to "The article mentions that."
[1]: https://news.ycombinator.com/newsguidelines.html