Left handed, right wrist.
That's me ....Right handed, watch on the left.
and that's SWMBO.Left handed, wear my watch on my right wrist.
Left handed, wear my watch on my right wrist.
I understand that it's all a matter of personal preference as there's no right answer. I'm just being a curious cat. It's like asking "When you cross your arms, which arm is on top?" Now try, crossing your arms with the other arm on top. It feels wrong, doesn't it?
It can be useful to switch things around. I recently discovered that if I wear some belts the opposite way round to my normal, the buckles lie flatter.
I tried folding my arms with the unusual arm on top - it actually took me several attempts to make it work!