Questions about horizontal paneling

[Frågvis]

Nail horizontal paneling

Should you nail together the horizontal panels (i.e., nail the panel on the long side with the one on the short side)?

It is common to do so with vertical paneling, but what about horizontal paneling?

 

[JesperS]

Don't know what is customary, but I don't have much ...

 

[snickarboden]

Why? You do have boards on the corners, right? Additionally, nails hold very poorly in end grain.

/Kent