Later, after I got married and my family spent a week every summer visiting my husband’s parents, I wondered why they sometimes drove around their small Virginia town in the early evening, with no errands to do, no people to meet, no specific destination.

Years later, I finally know the answers to these questions—and many others. It’s not that rituals and park benches have changed; rather, my perspectives have. Things that didn’t make sense to my younger self now make perfect sense.

All of which speaks to a larger discovery: that the ability to connect the dots between earlier and later decades—to see the intention behind actions that once seemed gratuitous—is one of the unanticipated benefits of getting older.

For instance, I get why those women haul around big muscle purses. It’s to provide room for a multitude of eyewear options—glasses for reading or for distance, glasses that can do both, sunglasses for reading or for distance, refresher drops, contact-lens cases, lens cleaners, wetting solutions. These pocketbooks double as portable eye-care repositories along with a place to stash keys, emergency snacks, change purses, makeup and other necessities.

Serenity now

Park benches are no longer puzzling. When I go on long walks to explore new cities, I look for benches where I can sit for a moment to catch my breath and take in the beauty and serenity of preserved green space. Isn’t this what parks are meant for?

Travel logistics: I understand that, too. With decades of travel experience behind us, we know that paying close attention to transportation details can make or break a trip, and getting to an unfamiliar place can be just as tricky, and hazardous, as actually being there.

Taking a drive at night around town? Now, decades later, my husband and I do the same thing when we go back to that same small town. It’s a sense of belonging to a place that holds many memories, of experiencing a quiet time of night when we can glide around neighborhoods and landmarks that look ageless at sunset. It’s a brief moment of feeling all is right with the world, even when, during the harsh light of day, we know that it isn’t.

Those examples are easy. Others are harder. At an earlier age, I didn’t see the need to write thank-you notes for gifts from grandparents at holiday time or graduation. It was considered proper “etiquette,” which meant doing things my mother felt were correct. Nor did I understand why it was important to send a note to a classmate whose father had passed away, or to the parents of my closest friend who died while we were in college.

I saw notes as awkward, embarrassing attempts to offer something meaningful when I had no idea what I should say, or what it meant to lose a person forever.

Now I know that reaching out to older people—even if briefly, awkwardly or late—establishes a lifeline that joins us in moments of celebration or grief. I understand that what takes little effort on a young person’s part offsets the indifference of a society that lacks respect for middle and older ages and the challenges they face.

These challenges include increasingly creaky bodies. In my 20s and 30s, I wondered why gatherings of older people so often became litanies of health-care woes—surgeries, accidents, medication mishaps, clueless doctors—even though these people invariably appeared (to me) healthy enough to discuss more pressing issues than hip replacement.

Nowadays, I can spend hours talking about the same topics. Every few weeks I have a “health lunch” with one particular friend, not to eat cauliflower and drink nut milk, but to check up on each other’s well-being, share media reports on the latest (often contradictory) research findings, and acknowledge that, at this point in our lives, unexpected health catastrophes can wreak havoc at any moment. We are grateful for each other.

Of course, certain quirky behaviors will always set older people up for dismissive eye rolls from younger generations. Some things I hope I never do: clog the checkout line at a drugstore while laboriously counting out 54 pennies in exact change; drive 10 miles an hour in a 35-mph zone; serve my children freezer-burned tuna noodle casserole.

A place for a vase

But there will always be truths, big and small, that resonate more clearly in the years ahead.

I understand now why members of the older generation sent me elegant monogrammed glassware as wedding gifts, when monograms back then seemed old-fashioned, even stodgy. They no longer feel that way, given the few opportunities I have to see my initials written anywhere, especially not in beautiful script. Yet those delicately entwined letters are part of my identity. They remind me of the day more than four decades ago that was the formal kickoff to a happy marriage.

A magazine article once described in detail the attention an older single woman gave to the placement of a vase containing her favorite flower, roses. As I remember it, two letters to the editor mocked her for spending so much time on such a trivial task when she could be focusing her energy on far more important undertakings. Weeks later, a third letter chastised those who begrudged this mindful moment—one woman’s attempt to create beauty and harmony in her home when the outside world offered little of either.

Older age offers new insights into many of life’s former mysteries. We appreciate a quiet evening drive, a note of acknowledgment, and we welcome the reassurance that a vase of flowers silhouetted against the morning sun can bring.

Ms. Shell is a writer in Philadelphia. She can be reached at reports@wsj.com.