If we have children and we teach them this custom of praying memorial services, we might have one or two generations praying for us after we die. And then we will most likely be forgotten unless we have a building in our name or were infamous for our stupidity. Otherwise there will be no memory of us and who will pray for us once we are gone and for the ages until the Second Coming... (Consider the generations you pray for... Parents, grandparents... probably no further down the ancestry tree.)
Hence, Memorial Services. Three of them.
And here we are, about to begin our Lenten Journey with death before us, which makes me think that the memorials are so aptly placed for our benefit as well. Nothing puts fire under a person's spiritual search and practice like reminding them they are going to die one day, like the family members generations before. With our own mortality in mind, worldly things are less important and we can look to preparing for the life after this one.
If you are interested in making the boiled wheat, Koliva, that is blessed during the Memorial Service, follow this link to an earlier post.