Three short lines carry a surprisingly large idea: almost everything people say, do, and are praised for disappears from human memory. Words fade, good deeds are overlooked, and even compliments are thrown away. The speaker doesn't shout about this. The tone is quiet and a little resigned, as if stating something long accepted.
The twist comes in the last line. Only "the sand" holds on to any of it. That's an odd and striking image, because sand is usually something that shifts, scatters, and wears away. It's hard to think of it as a keeper of memories. Yet the poem suggests that the natural world, vast and patient, absorbs what people let go. Perhaps sand is imagined as a record of footprints, or as a silent witness to time passing.
The mood is calm, wistful, and slightly lonely. There's sadness in how easily human effort is forgotten, but also an odd comfort in the idea that something, however unlikely, still remembers. The subtitle "Memory" points the reader straight to that tension.