The poem sets two states side by side: being emotionally attached, and being sealed off. In the first, the speaker says, a person "may slip and slide" because they are "tied to the tendrils of the heart." The image of tendrils suggests something delicate and living, like a climbing plant, and being tied to it means feeling is never steady. Love or deep attachment makes you stumble.
Then the poem turns. Inside "the glass ball," every step "attains a perfect landing." Glass is clear but protective, so this world looks flawless and controlled, yet it is also enclosed and a little artificial. The speaker doesn't say which life is better, and that leaves the poem open. The mood is quiet, wistful, and slightly ironic: a perfect landing sounds appealing, but it comes at the cost of the messy, risky pull of the heart. Readers may feel both the appeal of safety and a hint of what is lost by choosing it.