It's almost always time. There are peak times when lots of people use HN and upvote- if you submit outside of those times your link is likely to decay quickly.

(That said, I wouldn't be surprised if there was a negative factor associated for forbes.com. They've basically sold out their brand to clickbait nonsense)

Looks to me that they just weren't attention grabbing headlines. There wasn't any indication in the first one that it was a Michael Dell quote, and the second one just sounds like a random analyst offering an opinion on what Dell should do (which is not very interesting).