The compression of a human life into a eulogy is an odd phenomenon.
75 or 80 years of life are packaged into an hour-long service with a fifteen-minute eulogy. It's hard to imagine it being done any differently, and yet it just seems like an impossible task to do well - how do you do justice to decades of life, of breathing in and out, of raising children, making dinners, wiping grandkids' noses, building houses, running marathons, knitting jumpers, growing roses, playing the organ?
The memories are always in the stories; never in mere 'attributes'. So in a sense the real 'eulogy' happens in the days, weeks, months, years that follow when friends come together and stories are shared. Or even when you're alone, and replay an episode from the person's life just in your own mind.
What does it teach me? That no eulogy will ever do justice to the person who has just died, and that the best thing I can do while I relate to any other living person is learn to be as fully present as possible.