CASETTA, Italy — Romano Camassi, a seismologist, picked up a sand-colored speck as he surveyed the damage from this week’s earthquake on the green mountain crest where the village of Casetta, now ruins, once perched.

“This is just ground, soil,” he said, sadly. “In so many buildings in this area, that was the material used to keep together the irregular stones found in the surroundings which people used to build their homes.”

Experts like Mr. Camassi, who was part of the first team from Italy’s Institute of Geophysics and Volcanology to arrive at the quake zone in central Italy, say the destruction was amplified by vulnerable buildings whose upgrades to anti-seismic codes were deemed too costly for many Italians to carry out, too complicated to finance and too cumbersome to get approved.

Italy is beloved for its rich architectural history. But that beauty comes at a steep price: both the lives lost when nature reminds its borrowers who is boss, and the money required in the attempt to even the scales.

The country has spent an average of 3.5 billion euros a year, or $3.9 billion, for the past 50 years to fix earthquake damage, according to the Italian Association of Builders. And, in the aftermath of Wednesday’s quake, Prime Minister Matteo Renzi announced yet another plan to rebuild and buttress Italy’s ancient infrastructure.