[Duncan Gillies MacLaurin]

Last lines are certainly an interesting subject.

The last line of many light-hearted poems is what makes the whole poem work. For example:

Rainbow

When you see
de rainbow
you know
God know
wha he doing -
one big smile
across the sky -
I tell you
God got style
the man got style

When you see
raincloud pass
and de rainbow
make a show
I tell you
is God doing
limbo
the man doing
limbo

But sometimes
you know
when I see
de rainbow
so full of glow
and curving
like she bearing child
I does want know
if God
ain’t a woman

If that is so
the woman got style
man she got style

John Agard, 1989

On the other end of the spectrum, elegiac poetry also often has a last line that comes as a shock. In A. E. Stallings' recent collection, Hapax, there's a lovely poem called "Visiting the Grave of Rupert Brooke" in which she retells the story of how Odysseus snared Achilles, who was dressed up as a girl, by putting a sword among gifts he'd laid out for the girls. She ends with: "But only old men made it home from Troy."

I think the last line often needs to be dramatic when a poem is especially light-hearted or especially elegiac. Otherwise, an overly dramatic last line is often too out of place. But it always has to give closure and/or take you back to the start of the poem again.

This is probably all very banal, but I wanted to chime in: last lines are what it's all about.

Duncan