One of the challenges in writing memoir about times long ago, is that memory fades, diminishes, wavers, and sometimes simply disappears and details fall by the wayside.
In any story the specificity of detail can not only make the scene come alive, but also brings “authority” to the author. In writing fiction, we can make the details up. Close your eyes, see a scene, and write the details. But in memoir, crafting detail can be challenging, especially when writing from memory of times many years, even decades ago.