Every word counts in poems

In poems, I agree that every word counts, and I mean 'every' word. Every word is condensed with meaning. Sometimes I need to read a poem three or four times, subsequently, narrowing it down to the words that gives the poem the most impact and meaning. I like Shakespeare. I believe he is a master in disguise when it comes to his work. As stated before, there are times like now that I need to read and reread what he has written, in order to benefit from the poem's message. Afterwards, the chances are good that I need to reread it again. Shakespeare's poem "That time of year thou mayst in me behold" is a poem about an aging / dying man seeing his youth passing by. The title is a give-a-way. He uses a lot of metaphors in his poem. Here are some examples of words I picked out of the poem. "yellow leaves, or none, or few, do hang" (line 2) describes a season such as late autumn (this might be obvious); and "Bare ruined choirs" (line 4) these are churches like Abbeys in Europe that either have been bombed out or are already in ruins; therefore, they have no roofs; and lastly "This" (line 13) possibly an identification expression to exemplify the poet's descending youth, but the word "This" could be debatable, but that's the meaning I'm giving it.