I have experienced many delays due to mechanical problems, and I fly at most once per year. There are more mechanical problems in the air than in the tunnels, in my view.
Take our honeymoon -- 1986. We were scheduled to fly from LGA to Montreal to Halifax to Sydney, Nova Scotia. But our Air Canada plane broke down at LGA. So Air Canada paid to put us on another airline. But its plane also had mechanical difficulties and left an hour late. We rushed through Montreal's airport, only to see our connecting plane pulling away from the gate.
No problem said the gate attendent. Air Canada would put us up in a hotel, and fly us to Nova Scotia the next morning. As he was phoning his supervisor about it, the plane returned to the gate -- mechanical problems! They had given our seat away, but someone else go off because it was too late to make their connections in Halifax, so we took their seat. Eventually they "fixed" the plane, and we went on our way, and they held the small plane to Sydney for our connection (amazingly, it worked).
Hasn't the average plane gotten older since then?