sometimes labels are a good thing
1. An identifying name
2. A general or descriptive heading
Poems were once known by their first lines or by the author and general subject. In Shakespeare's time, titling a poem separately became popular.
Some poets complete a poem without adding a title, but a smart poet uses a title to lure the reader into the poem. Your title can be used to define the work, or be a tease with a hint about the subject of the poem. It can summarize the piece, or be a play on words.
Sometimes the title is the poem's first line, and is meant to be read as such, though I think this leads to confusion for the reader.
Regardless of the way you choose your title, remember that, particularly in the realm of internet poetry and forums, your title may be the thing that decides whether anyone reads your poem at all. Make the title interesting, something to give a reader reason to open the page and read it. Avoid the mundane or cliché. Use an interesting title to be 'advertisement' of sorts, to sell your work to the reader.