Clearly it is only a very confident or foolhardy poet that debates the true nature of poetry in their own work, as they obviously invite criticism of their poetry through holding up their own work as an example of good poetry. The criteria that Elizabeth Barrett Browning suggests are the hallmark of "good" poetry are actually rather hard to measure or quantify. She states that good poetry teaches "essential truths" to mankind about what it is to be human, and enlarges our understanding of the divine, which are rather abstract qualities.
In addition, she argues that good poetry will have a particularly emotional response on the reader, which she defines in her own experience as follows:
But the sun was high
When first I felt my pulses set themselves
For concords; when the rhythmic turbulence
Of blood and brain swept outward upon words,
As wind upon the alders blanching them
By turning up their under-natures till
They trembled in dilation.
Again, it is difficult to "measure" the impact that a poem has on us, and of course, given the very different nature of humans, one could argue that good poetry cannot be merely defined by whether or not it has a similar impact.
However, moving away from the subjective nature of her criteria, perhaps we can take from her definition of good poetry some statements that might help us to analyse poetry. Does it help us to understand more about the condition of being human? Does it create some kind of emotional response in us that strikes a chord with who we are? Such questions might be useful in order to take the heart of what Elizabeth Barrett Browning calls "good poetry" and use it as a measuring rod to assess other poems.