Intro patter that is backstory not visible in the poem is one thing.
Where you give away ending of the poem in the introduction thus undermining the effect is another.
Here’s a third way prefaces to poems can harm the effectiveness of the reading: Some months ago a poet explained an lexicon of terms, not characters only but also general vocabulary.
It struck me as long-winded, taking time that could be spent on the poetry. Was it more? Patronizing but that could be nervousness, a reader falling back on habit of other role as authority and teacher, mistaking the reading for a lecture.
It’s partly that, but I’ve put my finger on the key issue now. If the poet speaks to the audience, he or she speaks what the audience can understand. If it’s assumed the audience can’t understand then it is the wrong poems for the audience.
In this case the poet low-balled the audience explaining the most commonplace things.
It brings the question of how do you know what someone else knows especially when in a roomful of strange faces? Almost without exception everyone in a room of a poetry reading is a poet. Maybe published, maybe doing decades of competent work and reading.
Too often a poet gets up and explains what a poetic form is, or some ubiquitous thing presuming an audience unfamiliar with poetry. If someone was dragged in by a coworker, a line of definition will not be enough. If the audience is familiar, a line will be too much.
You want to make everyone feel included. It’s rare for someone to be attending their first reading. Every individual is the core audience but so is the third person in the group, the average personality of the crowd.
Poems meant for slow re-read of the eyes may not translate well to the quick air.
If most of your poems are not for oral, it misrepresents the book to choose only those most similar to the medium of easy to the ear.
Is it not best to present the poem straight out? It will entice with what was partially caught, or the whole will be caught but if it doesn’t stand alone, there’s no way to remedy that at this stage. Plough on.
If the poem is structured with such difficulty that one pass isn’t enough the grasp its outlines or energy, that’s the concern of another day.
Every reading will not be outstanding. Sometimes there’s an off energy within the reader so he or she can’t stay present in the poems. Sometimes the audience, that third collective energy, will get the poems and feedback loop beautifully. Sometimes it won’t. That’s not in the poet’s control or the poems. There’s ultimately just doing it.

I made an infographic map of haiku and related forms. Some influenced haiku or were influenced by, some derived from, some share a common ancestor of ancient Chinese court poetry.

It’s a projection map where haiku is large and central because it is a map of haiku. If tanka were the centre or concrete poetry proportions would be different.