Robert Frost on Poetry: "It begins with a lump in the throat, a sense of wrong, a homesickness, a lovesickness. It is never a thought to begin with."
I'm not a poet unless you count making up silly limericks and lame versions of "roses are red." But I love poetry and I adore this Robert Frost quote!
To me it's a perfect description why it's hard to just sit down to write a poem. School assignments were tough that demanded "on call" emotion to emerge on the ready! The great poems seem to germinate from that lump or that longing.
Or rather, I've heard it said: "the poem finds us!"
Sounds about right!