I left Slashdot for HN...but I didn't leave Slashdot because of HN. I was frustrated with Slashdot and was actively seeking alternatives. About 2 days after I discovered HN existed, I was done forever with Slashdot.

Among other frustrations (including some really vile comments), I felt like the world was bursting with interesting tech news, and Slashdot was just not keeping up. The publish rate was too slow (maybe 10-13 stories a day), and the %age of stories I found interesting had dropped considerably from a few years previous.

I wasn't a fan of the redesign, but it was content that drove me to seek alternatives.