Not long ago, I had to maintain a small vacant mobile home for several years.
Hundreds of dollars were spent just keeping air conditioning going, to keep the interior fresh and protected from moisture, mold, decay and pests.
A leak developed in the roof, and the repair required a few thousand dollars for materials and labor.
SO THE POINT IS, buildings, structures, infrastructure and many other things need to be MAINTAINED.
MAINTENANCE, MAINTENANCE, MAINTENANCE!
For whatever it is you want to keep functional and in proper working order, an ongoing commitment of maintenance is necessary. Until you're ready to abandon or otherwise dispose of that which requires maintenance.
When it comes to roads and bridges, its a never ending battle to keep them repaired and safe.
Unfortunately, maintenance often fails to keep up with necessary repairs and upgrades.
It seems that San Francisco's Golden Gate Bridge is beginning to deteriorate.
In the first video below, it even appears the road approaching the bridge could use some new surfacing work.
To keep the bridge in good shape, it requires removing the old paint, removing/sanding/blasting corrosion away, smoothing the steel surfaces, adding two primer coats, plus two coats of specially formulated and colored paints.
The Golden Gate Bridge opened in 1937, and if it is going to survive another 80+ years, it's going to be very expensive and the task monumental.