system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Why does skin heal more slowly the older you get?

I'm turning 40 this year, and I'm noticing that the nicks and cuts I'm used to getting which have always healed really quickly are leaving more scars and lasting longer than they have in the past. Im outdoors active, and accrue more than a few cuts often on my lower legs. Is this a natural part of growing old, which is in line with my observations of my parents' skin as well, or am I not caring for my skin well?
gpt
Think of your cells dividing as a printer making paper copies. A copy can only be as good as the original but usually you lose a bit of quality.

Over time, the original document wears out and you're making copies of copies. Each copies need to be a certain quality level or else they're rejected. As you make more and more copies, the reject rate increases over time.

Your dividing cells undergo a check to make sure they're copied properly. If they fail, they undergo planned cell suicide (apoptosis) and are recycled. As you age, a larger percentage of dividing cells fail the check because of DNA wearing out from copying, making it harder to increase the number of good cells to heal a wound.