[ionised]

I have multiple email address for different purposes. I don't need multiple HN accounts for different purposes.

Others might but I can't think why off the top of my head. The only time I've seen an obvious alternate account is the throw-away accounts opened just to troll/spam the site.

[joering2]

One example would be is that you might work for a company and have their point of view expressed on HN all the time; meanwhile you want to have your own account personal one that regardless if you continue working for said company or not, you still continue to use. Sort of like TV anchors have their own private twitter hints and then they have their work ones too.

[ionised]

That makes sense.